David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1 | /* |
| 2 | * at91_can.c - CAN network driver for AT91 SoC CAN controller |
| 3 | * |
Hans J. Koch | 3e9ebd3 | 2010-10-29 12:33:57 +0000 | [diff] [blame] | 4 | * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de> |
Marc Kleine-Budde | 0909c1e | 2011-01-06 09:58:42 +0100 | [diff] [blame] | 5 | * (C) 2008, 2009, 2010, 2011 by Marc Kleine-Budde <kernel@pengutronix.de> |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 6 | * |
| 7 | * This software may be distributed under the terms of the GNU General |
| 8 | * Public License ("GPL") version 2 as distributed in the 'COPYING' |
| 9 | * file from the main directory of the linux kernel source. |
| 10 | * |
| 11 | * Send feedback to <socketcan-users@lists.berlios.de> |
| 12 | * |
| 13 | * |
| 14 | * Your platform definition file should specify something like: |
| 15 | * |
| 16 | * static struct at91_can_data ek_can_data = { |
| 17 | * transceiver_switch = sam9263ek_transceiver_switch, |
| 18 | * }; |
| 19 | * |
| 20 | * at91_add_device_can(&ek_can_data); |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include <linux/clk.h> |
| 25 | #include <linux/errno.h> |
| 26 | #include <linux/if_arp.h> |
| 27 | #include <linux/init.h> |
| 28 | #include <linux/interrupt.h> |
| 29 | #include <linux/kernel.h> |
| 30 | #include <linux/module.h> |
| 31 | #include <linux/netdevice.h> |
| 32 | #include <linux/platform_device.h> |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 33 | #include <linux/rtnetlink.h> |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 34 | #include <linux/skbuff.h> |
| 35 | #include <linux/spinlock.h> |
| 36 | #include <linux/string.h> |
| 37 | #include <linux/types.h> |
| 38 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 39 | #include <linux/can/dev.h> |
| 40 | #include <linux/can/error.h> |
| 41 | |
| 42 | #include <mach/board.h> |
| 43 | |
Marc Kleine-Budde | b049994 | 2011-05-03 16:37:16 +0200 | [diff] [blame] | 44 | #define AT91_MB_MASK(i) ((1 << (i)) - 1) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 45 | |
| 46 | /* Common registers */ |
| 47 | enum at91_reg { |
| 48 | AT91_MR = 0x000, |
| 49 | AT91_IER = 0x004, |
| 50 | AT91_IDR = 0x008, |
| 51 | AT91_IMR = 0x00C, |
| 52 | AT91_SR = 0x010, |
| 53 | AT91_BR = 0x014, |
| 54 | AT91_TIM = 0x018, |
| 55 | AT91_TIMESTP = 0x01C, |
| 56 | AT91_ECR = 0x020, |
| 57 | AT91_TCR = 0x024, |
| 58 | AT91_ACR = 0x028, |
| 59 | }; |
| 60 | |
| 61 | /* Mailbox registers (0 <= i <= 15) */ |
| 62 | #define AT91_MMR(i) (enum at91_reg)(0x200 + ((i) * 0x20)) |
| 63 | #define AT91_MAM(i) (enum at91_reg)(0x204 + ((i) * 0x20)) |
| 64 | #define AT91_MID(i) (enum at91_reg)(0x208 + ((i) * 0x20)) |
| 65 | #define AT91_MFID(i) (enum at91_reg)(0x20C + ((i) * 0x20)) |
| 66 | #define AT91_MSR(i) (enum at91_reg)(0x210 + ((i) * 0x20)) |
| 67 | #define AT91_MDL(i) (enum at91_reg)(0x214 + ((i) * 0x20)) |
| 68 | #define AT91_MDH(i) (enum at91_reg)(0x218 + ((i) * 0x20)) |
| 69 | #define AT91_MCR(i) (enum at91_reg)(0x21C + ((i) * 0x20)) |
| 70 | |
| 71 | /* Register bits */ |
| 72 | #define AT91_MR_CANEN BIT(0) |
| 73 | #define AT91_MR_LPM BIT(1) |
| 74 | #define AT91_MR_ABM BIT(2) |
| 75 | #define AT91_MR_OVL BIT(3) |
| 76 | #define AT91_MR_TEOF BIT(4) |
| 77 | #define AT91_MR_TTM BIT(5) |
| 78 | #define AT91_MR_TIMFRZ BIT(6) |
| 79 | #define AT91_MR_DRPT BIT(7) |
| 80 | |
| 81 | #define AT91_SR_RBSY BIT(29) |
| 82 | |
| 83 | #define AT91_MMR_PRIO_SHIFT (16) |
| 84 | |
| 85 | #define AT91_MID_MIDE BIT(29) |
| 86 | |
| 87 | #define AT91_MSR_MRTR BIT(20) |
| 88 | #define AT91_MSR_MABT BIT(22) |
| 89 | #define AT91_MSR_MRDY BIT(23) |
| 90 | #define AT91_MSR_MMI BIT(24) |
| 91 | |
| 92 | #define AT91_MCR_MRTR BIT(20) |
| 93 | #define AT91_MCR_MTCR BIT(23) |
| 94 | |
| 95 | /* Mailbox Modes */ |
| 96 | enum at91_mb_mode { |
| 97 | AT91_MB_MODE_DISABLED = 0, |
| 98 | AT91_MB_MODE_RX = 1, |
| 99 | AT91_MB_MODE_RX_OVRWR = 2, |
| 100 | AT91_MB_MODE_TX = 3, |
| 101 | AT91_MB_MODE_CONSUMER = 4, |
| 102 | AT91_MB_MODE_PRODUCER = 5, |
| 103 | }; |
| 104 | |
| 105 | /* Interrupt mask bits */ |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 106 | #define AT91_IRQ_ERRA (1 << 16) |
| 107 | #define AT91_IRQ_WARN (1 << 17) |
| 108 | #define AT91_IRQ_ERRP (1 << 18) |
| 109 | #define AT91_IRQ_BOFF (1 << 19) |
| 110 | #define AT91_IRQ_SLEEP (1 << 20) |
| 111 | #define AT91_IRQ_WAKEUP (1 << 21) |
| 112 | #define AT91_IRQ_TOVF (1 << 22) |
| 113 | #define AT91_IRQ_TSTP (1 << 23) |
| 114 | #define AT91_IRQ_CERR (1 << 24) |
| 115 | #define AT91_IRQ_SERR (1 << 25) |
| 116 | #define AT91_IRQ_AERR (1 << 26) |
| 117 | #define AT91_IRQ_FERR (1 << 27) |
| 118 | #define AT91_IRQ_BERR (1 << 28) |
| 119 | |
| 120 | #define AT91_IRQ_ERR_ALL (0x1fff0000) |
| 121 | #define AT91_IRQ_ERR_FRAME (AT91_IRQ_CERR | AT91_IRQ_SERR | \ |
| 122 | AT91_IRQ_AERR | AT91_IRQ_FERR | AT91_IRQ_BERR) |
| 123 | #define AT91_IRQ_ERR_LINE (AT91_IRQ_ERRA | AT91_IRQ_WARN | \ |
| 124 | AT91_IRQ_ERRP | AT91_IRQ_BOFF) |
| 125 | |
| 126 | #define AT91_IRQ_ALL (0x1fffffff) |
| 127 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 128 | enum at91_devtype { |
| 129 | AT91_DEVTYPE_SAM9263, |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 130 | AT91_DEVTYPE_SAM9X5, |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 131 | }; |
| 132 | |
| 133 | struct at91_devtype_data { |
| 134 | unsigned int rx_first; |
| 135 | unsigned int rx_split; |
| 136 | unsigned int rx_last; |
| 137 | unsigned int tx_shift; |
| 138 | enum at91_devtype type; |
| 139 | }; |
| 140 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 141 | struct at91_priv { |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 142 | struct can_priv can; /* must be the first member! */ |
| 143 | struct net_device *dev; |
| 144 | struct napi_struct napi; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 145 | |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 146 | void __iomem *reg_base; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 147 | |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 148 | u32 reg_sr; |
| 149 | unsigned int tx_next; |
| 150 | unsigned int tx_echo; |
| 151 | unsigned int rx_next; |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 152 | struct at91_devtype_data devtype_data; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 153 | |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 154 | struct clk *clk; |
| 155 | struct at91_can_data *pdata; |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 156 | |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 157 | canid_t mb0_id; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 158 | }; |
| 159 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 160 | static const struct at91_devtype_data at91_devtype_data[] __devinitconst = { |
| 161 | [AT91_DEVTYPE_SAM9263] = { |
| 162 | .rx_first = 1, |
| 163 | .rx_split = 8, |
| 164 | .rx_last = 11, |
| 165 | .tx_shift = 2, |
| 166 | }, |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 167 | [AT91_DEVTYPE_SAM9X5] = { |
| 168 | .rx_first = 0, |
| 169 | .rx_split = 4, |
| 170 | .rx_last = 5, |
| 171 | .tx_shift = 1, |
| 172 | }, |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 173 | }; |
| 174 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 175 | static struct can_bittiming_const at91_bittiming_const = { |
Marc Kleine-Budde | 00389b0 | 2010-10-21 01:01:22 +0000 | [diff] [blame] | 176 | .name = KBUILD_MODNAME, |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 177 | .tseg1_min = 4, |
| 178 | .tseg1_max = 16, |
| 179 | .tseg2_min = 2, |
| 180 | .tseg2_max = 8, |
| 181 | .sjw_max = 4, |
| 182 | .brp_min = 2, |
| 183 | .brp_max = 128, |
| 184 | .brp_inc = 1, |
| 185 | }; |
| 186 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 187 | #define AT91_IS(_model) \ |
| 188 | static inline int at91_is_sam##_model(const struct at91_priv *priv) \ |
| 189 | { \ |
| 190 | return priv->devtype_data.type == AT91_DEVTYPE_SAM##_model; \ |
| 191 | } |
| 192 | |
| 193 | AT91_IS(9263); |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 194 | AT91_IS(9X5); |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 195 | |
| 196 | static inline unsigned int get_mb_rx_first(const struct at91_priv *priv) |
| 197 | { |
| 198 | return priv->devtype_data.rx_first; |
| 199 | } |
| 200 | |
| 201 | static inline unsigned int get_mb_rx_last(const struct at91_priv *priv) |
| 202 | { |
| 203 | return priv->devtype_data.rx_last; |
| 204 | } |
| 205 | |
| 206 | static inline unsigned int get_mb_rx_split(const struct at91_priv *priv) |
| 207 | { |
| 208 | return priv->devtype_data.rx_split; |
| 209 | } |
| 210 | |
| 211 | static inline unsigned int get_mb_rx_num(const struct at91_priv *priv) |
| 212 | { |
| 213 | return get_mb_rx_last(priv) - get_mb_rx_first(priv) + 1; |
| 214 | } |
| 215 | |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 216 | static inline unsigned int get_mb_rx_low_last(const struct at91_priv *priv) |
| 217 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 218 | return get_mb_rx_split(priv) - 1; |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 219 | } |
| 220 | |
| 221 | static inline unsigned int get_mb_rx_low_mask(const struct at91_priv *priv) |
| 222 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 223 | return AT91_MB_MASK(get_mb_rx_split(priv)) & |
| 224 | ~AT91_MB_MASK(get_mb_rx_first(priv)); |
| 225 | } |
| 226 | |
| 227 | static inline unsigned int get_mb_tx_shift(const struct at91_priv *priv) |
| 228 | { |
| 229 | return priv->devtype_data.tx_shift; |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 230 | } |
| 231 | |
| 232 | static inline unsigned int get_mb_tx_num(const struct at91_priv *priv) |
| 233 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 234 | return 1 << get_mb_tx_shift(priv); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 235 | } |
| 236 | |
| 237 | static inline unsigned int get_mb_tx_first(const struct at91_priv *priv) |
| 238 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 239 | return get_mb_rx_last(priv) + 1; |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 240 | } |
| 241 | |
| 242 | static inline unsigned int get_mb_tx_last(const struct at91_priv *priv) |
| 243 | { |
| 244 | return get_mb_tx_first(priv) + get_mb_tx_num(priv) - 1; |
| 245 | } |
| 246 | |
| 247 | static inline unsigned int get_next_prio_shift(const struct at91_priv *priv) |
| 248 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 249 | return get_mb_tx_shift(priv); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 250 | } |
| 251 | |
| 252 | static inline unsigned int get_next_prio_mask(const struct at91_priv *priv) |
| 253 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 254 | return 0xf << get_mb_tx_shift(priv); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 255 | } |
| 256 | |
| 257 | static inline unsigned int get_next_mb_mask(const struct at91_priv *priv) |
| 258 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 259 | return AT91_MB_MASK(get_mb_tx_shift(priv)); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 260 | } |
| 261 | |
| 262 | static inline unsigned int get_next_mask(const struct at91_priv *priv) |
| 263 | { |
| 264 | return get_next_mb_mask(priv) | get_next_prio_mask(priv); |
| 265 | } |
| 266 | |
| 267 | static inline unsigned int get_irq_mb_rx(const struct at91_priv *priv) |
| 268 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 269 | return AT91_MB_MASK(get_mb_rx_last(priv) + 1) & |
| 270 | ~AT91_MB_MASK(get_mb_rx_first(priv)); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 271 | } |
| 272 | |
| 273 | static inline unsigned int get_irq_mb_tx(const struct at91_priv *priv) |
| 274 | { |
| 275 | return AT91_MB_MASK(get_mb_tx_last(priv) + 1) & |
| 276 | ~AT91_MB_MASK(get_mb_tx_first(priv)); |
| 277 | } |
| 278 | |
Marc Kleine-Budde | 9c2e0a6 | 2011-05-03 17:47:55 +0200 | [diff] [blame] | 279 | static inline unsigned int get_tx_next_mb(const struct at91_priv *priv) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 280 | { |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 281 | return (priv->tx_next & get_next_mb_mask(priv)) + get_mb_tx_first(priv); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 282 | } |
| 283 | |
Marc Kleine-Budde | 9c2e0a6 | 2011-05-03 17:47:55 +0200 | [diff] [blame] | 284 | static inline unsigned int get_tx_next_prio(const struct at91_priv *priv) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 285 | { |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 286 | return (priv->tx_next >> get_next_prio_shift(priv)) & 0xf; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 287 | } |
| 288 | |
Marc Kleine-Budde | 9c2e0a6 | 2011-05-03 17:47:55 +0200 | [diff] [blame] | 289 | static inline unsigned int get_tx_echo_mb(const struct at91_priv *priv) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 290 | { |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 291 | return (priv->tx_echo & get_next_mb_mask(priv)) + get_mb_tx_first(priv); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | static inline u32 at91_read(const struct at91_priv *priv, enum at91_reg reg) |
| 295 | { |
Marc Kleine-Budde | 7672fe7 | 2010-10-21 01:01:20 +0000 | [diff] [blame] | 296 | return __raw_readl(priv->reg_base + reg); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 297 | } |
| 298 | |
| 299 | static inline void at91_write(const struct at91_priv *priv, enum at91_reg reg, |
| 300 | u32 value) |
| 301 | { |
Marc Kleine-Budde | 7672fe7 | 2010-10-21 01:01:20 +0000 | [diff] [blame] | 302 | __raw_writel(value, priv->reg_base + reg); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 303 | } |
| 304 | |
| 305 | static inline void set_mb_mode_prio(const struct at91_priv *priv, |
| 306 | unsigned int mb, enum at91_mb_mode mode, int prio) |
| 307 | { |
| 308 | at91_write(priv, AT91_MMR(mb), (mode << 24) | (prio << 16)); |
| 309 | } |
| 310 | |
| 311 | static inline void set_mb_mode(const struct at91_priv *priv, unsigned int mb, |
| 312 | enum at91_mb_mode mode) |
| 313 | { |
| 314 | set_mb_mode_prio(priv, mb, mode, 0); |
| 315 | } |
| 316 | |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 317 | static inline u32 at91_can_id_to_reg_mid(canid_t can_id) |
| 318 | { |
| 319 | u32 reg_mid; |
| 320 | |
| 321 | if (can_id & CAN_EFF_FLAG) |
| 322 | reg_mid = (can_id & CAN_EFF_MASK) | AT91_MID_MIDE; |
| 323 | else |
| 324 | reg_mid = (can_id & CAN_SFF_MASK) << 18; |
| 325 | |
| 326 | return reg_mid; |
| 327 | } |
| 328 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 329 | /* |
| 330 | * Swtich transceiver on or off |
| 331 | */ |
| 332 | static void at91_transceiver_switch(const struct at91_priv *priv, int on) |
| 333 | { |
| 334 | if (priv->pdata && priv->pdata->transceiver_switch) |
| 335 | priv->pdata->transceiver_switch(on); |
| 336 | } |
| 337 | |
| 338 | static void at91_setup_mailboxes(struct net_device *dev) |
| 339 | { |
| 340 | struct at91_priv *priv = netdev_priv(dev); |
| 341 | unsigned int i; |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 342 | u32 reg_mid; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 343 | |
| 344 | /* |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 345 | * Due to a chip bug (errata 50.2.6.3 & 50.3.5.3) the first |
| 346 | * mailbox is disabled. The next 11 mailboxes are used as a |
| 347 | * reception FIFO. The last mailbox is configured with |
| 348 | * overwrite option. The overwrite flag indicates a FIFO |
| 349 | * overflow. |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 350 | */ |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 351 | reg_mid = at91_can_id_to_reg_mid(priv->mb0_id); |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 352 | for (i = 0; i < get_mb_rx_first(priv); i++) { |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 353 | set_mb_mode(priv, i, AT91_MB_MODE_DISABLED); |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 354 | at91_write(priv, AT91_MID(i), reg_mid); |
| 355 | at91_write(priv, AT91_MCR(i), 0x0); /* clear dlc */ |
| 356 | } |
| 357 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 358 | for (i = get_mb_rx_first(priv); i < get_mb_rx_last(priv); i++) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 359 | set_mb_mode(priv, i, AT91_MB_MODE_RX); |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 360 | set_mb_mode(priv, get_mb_rx_last(priv), AT91_MB_MODE_RX_OVRWR); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 361 | |
Marc Kleine-Budde | 8a0e0a4 | 2010-10-21 01:01:14 +0000 | [diff] [blame] | 362 | /* reset acceptance mask and id register */ |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 363 | for (i = get_mb_rx_first(priv); i <= get_mb_rx_last(priv); i++) { |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 364 | at91_write(priv, AT91_MAM(i), 0x0); |
Marc Kleine-Budde | 8a0e0a4 | 2010-10-21 01:01:14 +0000 | [diff] [blame] | 365 | at91_write(priv, AT91_MID(i), AT91_MID_MIDE); |
| 366 | } |
| 367 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 368 | /* The last 4 mailboxes are used for transmitting. */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 369 | for (i = get_mb_tx_first(priv); i <= get_mb_tx_last(priv); i++) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 370 | set_mb_mode_prio(priv, i, AT91_MB_MODE_TX, 0); |
| 371 | |
| 372 | /* Reset tx and rx helper pointers */ |
Marc Kleine-Budde | 0909c1e | 2011-01-06 09:58:42 +0100 | [diff] [blame] | 373 | priv->tx_next = priv->tx_echo = 0; |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 374 | priv->rx_next = get_mb_rx_first(priv); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 375 | } |
| 376 | |
| 377 | static int at91_set_bittiming(struct net_device *dev) |
| 378 | { |
| 379 | const struct at91_priv *priv = netdev_priv(dev); |
| 380 | const struct can_bittiming *bt = &priv->can.bittiming; |
| 381 | u32 reg_br; |
| 382 | |
Marc Kleine-Budde | dbe9132 | 2010-10-21 01:01:13 +0000 | [diff] [blame] | 383 | reg_br = ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) ? 1 << 24 : 0) | |
| 384 | ((bt->brp - 1) << 16) | ((bt->sjw - 1) << 12) | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 385 | ((bt->prop_seg - 1) << 8) | ((bt->phase_seg1 - 1) << 4) | |
| 386 | ((bt->phase_seg2 - 1) << 0); |
| 387 | |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 388 | netdev_info(dev, "writing AT91_BR: 0x%08x\n", reg_br); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 389 | |
| 390 | at91_write(priv, AT91_BR, reg_br); |
| 391 | |
| 392 | return 0; |
| 393 | } |
| 394 | |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 395 | static int at91_get_berr_counter(const struct net_device *dev, |
| 396 | struct can_berr_counter *bec) |
| 397 | { |
| 398 | const struct at91_priv *priv = netdev_priv(dev); |
| 399 | u32 reg_ecr = at91_read(priv, AT91_ECR); |
| 400 | |
| 401 | bec->rxerr = reg_ecr & 0xff; |
| 402 | bec->txerr = reg_ecr >> 16; |
| 403 | |
| 404 | return 0; |
| 405 | } |
| 406 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 407 | static void at91_chip_start(struct net_device *dev) |
| 408 | { |
| 409 | struct at91_priv *priv = netdev_priv(dev); |
| 410 | u32 reg_mr, reg_ier; |
| 411 | |
| 412 | /* disable interrupts */ |
| 413 | at91_write(priv, AT91_IDR, AT91_IRQ_ALL); |
| 414 | |
| 415 | /* disable chip */ |
| 416 | reg_mr = at91_read(priv, AT91_MR); |
| 417 | at91_write(priv, AT91_MR, reg_mr & ~AT91_MR_CANEN); |
| 418 | |
Marc Kleine-Budde | b156fd0 | 2010-10-21 01:01:19 +0000 | [diff] [blame] | 419 | at91_set_bittiming(dev); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 420 | at91_setup_mailboxes(dev); |
| 421 | at91_transceiver_switch(priv, 1); |
| 422 | |
| 423 | /* enable chip */ |
| 424 | at91_write(priv, AT91_MR, AT91_MR_CANEN); |
| 425 | |
| 426 | priv->can.state = CAN_STATE_ERROR_ACTIVE; |
| 427 | |
| 428 | /* Enable interrupts */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 429 | reg_ier = get_irq_mb_rx(priv) | AT91_IRQ_ERRP | AT91_IRQ_ERR_FRAME; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 430 | at91_write(priv, AT91_IDR, AT91_IRQ_ALL); |
| 431 | at91_write(priv, AT91_IER, reg_ier); |
| 432 | } |
| 433 | |
| 434 | static void at91_chip_stop(struct net_device *dev, enum can_state state) |
| 435 | { |
| 436 | struct at91_priv *priv = netdev_priv(dev); |
| 437 | u32 reg_mr; |
| 438 | |
| 439 | /* disable interrupts */ |
| 440 | at91_write(priv, AT91_IDR, AT91_IRQ_ALL); |
| 441 | |
| 442 | reg_mr = at91_read(priv, AT91_MR); |
| 443 | at91_write(priv, AT91_MR, reg_mr & ~AT91_MR_CANEN); |
| 444 | |
| 445 | at91_transceiver_switch(priv, 0); |
| 446 | priv->can.state = state; |
| 447 | } |
| 448 | |
| 449 | /* |
| 450 | * theory of operation: |
| 451 | * |
| 452 | * According to the datasheet priority 0 is the highest priority, 15 |
| 453 | * is the lowest. If two mailboxes have the same priority level the |
| 454 | * message of the mailbox with the lowest number is sent first. |
| 455 | * |
| 456 | * We use the first TX mailbox (AT91_MB_TX_FIRST) with prio 0, then |
| 457 | * the next mailbox with prio 0, and so on, until all mailboxes are |
| 458 | * used. Then we start from the beginning with mailbox |
| 459 | * AT91_MB_TX_FIRST, but with prio 1, mailbox AT91_MB_TX_FIRST + 1 |
| 460 | * prio 1. When we reach the last mailbox with prio 15, we have to |
| 461 | * stop sending, waiting for all messages to be delivered, then start |
| 462 | * again with mailbox AT91_MB_TX_FIRST prio 0. |
| 463 | * |
| 464 | * We use the priv->tx_next as counter for the next transmission |
| 465 | * mailbox, but without the offset AT91_MB_TX_FIRST. The lower bits |
| 466 | * encode the mailbox number, the upper 4 bits the mailbox priority: |
| 467 | * |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 468 | * priv->tx_next = (prio << get_next_prio_shift(priv)) | |
| 469 | * (mb - get_mb_tx_first(priv)); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 470 | * |
| 471 | */ |
| 472 | static netdev_tx_t at91_start_xmit(struct sk_buff *skb, struct net_device *dev) |
| 473 | { |
| 474 | struct at91_priv *priv = netdev_priv(dev); |
| 475 | struct net_device_stats *stats = &dev->stats; |
| 476 | struct can_frame *cf = (struct can_frame *)skb->data; |
| 477 | unsigned int mb, prio; |
| 478 | u32 reg_mid, reg_mcr; |
| 479 | |
Oliver Hartkopp | 3ccd4c6 | 2010-01-12 02:00:46 -0800 | [diff] [blame] | 480 | if (can_dropped_invalid_skb(dev, skb)) |
| 481 | return NETDEV_TX_OK; |
| 482 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 483 | mb = get_tx_next_mb(priv); |
| 484 | prio = get_tx_next_prio(priv); |
| 485 | |
| 486 | if (unlikely(!(at91_read(priv, AT91_MSR(mb)) & AT91_MSR_MRDY))) { |
| 487 | netif_stop_queue(dev); |
| 488 | |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 489 | netdev_err(dev, "BUG! TX buffer full when queue awake!\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 490 | return NETDEV_TX_BUSY; |
| 491 | } |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 492 | reg_mid = at91_can_id_to_reg_mid(cf->can_id); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 493 | reg_mcr = ((cf->can_id & CAN_RTR_FLAG) ? AT91_MCR_MRTR : 0) | |
| 494 | (cf->can_dlc << 16) | AT91_MCR_MTCR; |
| 495 | |
| 496 | /* disable MB while writing ID (see datasheet) */ |
| 497 | set_mb_mode(priv, mb, AT91_MB_MODE_DISABLED); |
| 498 | at91_write(priv, AT91_MID(mb), reg_mid); |
| 499 | set_mb_mode_prio(priv, mb, AT91_MB_MODE_TX, prio); |
| 500 | |
| 501 | at91_write(priv, AT91_MDL(mb), *(u32 *)(cf->data + 0)); |
| 502 | at91_write(priv, AT91_MDH(mb), *(u32 *)(cf->data + 4)); |
| 503 | |
| 504 | /* This triggers transmission */ |
| 505 | at91_write(priv, AT91_MCR(mb), reg_mcr); |
| 506 | |
| 507 | stats->tx_bytes += cf->can_dlc; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 508 | |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 509 | /* _NOTE_: subtract AT91_MB_TX_FIRST offset from mb! */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 510 | can_put_echo_skb(skb, dev, mb - get_mb_tx_first(priv)); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 511 | |
| 512 | /* |
| 513 | * we have to stop the queue and deliver all messages in case |
| 514 | * of a prio+mb counter wrap around. This is the case if |
| 515 | * tx_next buffer prio and mailbox equals 0. |
| 516 | * |
| 517 | * also stop the queue if next buffer is still in use |
| 518 | * (== not ready) |
| 519 | */ |
| 520 | priv->tx_next++; |
| 521 | if (!(at91_read(priv, AT91_MSR(get_tx_next_mb(priv))) & |
| 522 | AT91_MSR_MRDY) || |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 523 | (priv->tx_next & get_next_mask(priv)) == 0) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 524 | netif_stop_queue(dev); |
| 525 | |
| 526 | /* Enable interrupt for this mailbox */ |
| 527 | at91_write(priv, AT91_IER, 1 << mb); |
| 528 | |
| 529 | return NETDEV_TX_OK; |
| 530 | } |
| 531 | |
| 532 | /** |
| 533 | * at91_activate_rx_low - activate lower rx mailboxes |
| 534 | * @priv: a91 context |
| 535 | * |
| 536 | * Reenables the lower mailboxes for reception of new CAN messages |
| 537 | */ |
| 538 | static inline void at91_activate_rx_low(const struct at91_priv *priv) |
| 539 | { |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 540 | u32 mask = get_mb_rx_low_mask(priv); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 541 | at91_write(priv, AT91_TCR, mask); |
| 542 | } |
| 543 | |
| 544 | /** |
| 545 | * at91_activate_rx_mb - reactive single rx mailbox |
| 546 | * @priv: a91 context |
| 547 | * @mb: mailbox to reactivate |
| 548 | * |
| 549 | * Reenables given mailbox for reception of new CAN messages |
| 550 | */ |
| 551 | static inline void at91_activate_rx_mb(const struct at91_priv *priv, |
| 552 | unsigned int mb) |
| 553 | { |
| 554 | u32 mask = 1 << mb; |
| 555 | at91_write(priv, AT91_TCR, mask); |
| 556 | } |
| 557 | |
| 558 | /** |
| 559 | * at91_rx_overflow_err - send error frame due to rx overflow |
| 560 | * @dev: net device |
| 561 | */ |
| 562 | static void at91_rx_overflow_err(struct net_device *dev) |
| 563 | { |
| 564 | struct net_device_stats *stats = &dev->stats; |
| 565 | struct sk_buff *skb; |
| 566 | struct can_frame *cf; |
| 567 | |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 568 | netdev_dbg(dev, "RX buffer overflow\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 569 | stats->rx_over_errors++; |
| 570 | stats->rx_errors++; |
| 571 | |
| 572 | skb = alloc_can_err_skb(dev, &cf); |
| 573 | if (unlikely(!skb)) |
| 574 | return; |
| 575 | |
| 576 | cf->can_id |= CAN_ERR_CRTL; |
| 577 | cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; |
| 578 | netif_receive_skb(skb); |
| 579 | |
| 580 | stats->rx_packets++; |
| 581 | stats->rx_bytes += cf->can_dlc; |
| 582 | } |
| 583 | |
| 584 | /** |
| 585 | * at91_read_mb - read CAN msg from mailbox (lowlevel impl) |
| 586 | * @dev: net device |
| 587 | * @mb: mailbox number to read from |
| 588 | * @cf: can frame where to store message |
| 589 | * |
| 590 | * Reads a CAN message from the given mailbox and stores data into |
| 591 | * given can frame. "mb" and "cf" must be valid. |
| 592 | */ |
| 593 | static void at91_read_mb(struct net_device *dev, unsigned int mb, |
| 594 | struct can_frame *cf) |
| 595 | { |
| 596 | const struct at91_priv *priv = netdev_priv(dev); |
| 597 | u32 reg_msr, reg_mid; |
| 598 | |
| 599 | reg_mid = at91_read(priv, AT91_MID(mb)); |
| 600 | if (reg_mid & AT91_MID_MIDE) |
| 601 | cf->can_id = ((reg_mid >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG; |
| 602 | else |
| 603 | cf->can_id = (reg_mid >> 18) & CAN_SFF_MASK; |
| 604 | |
| 605 | reg_msr = at91_read(priv, AT91_MSR(mb)); |
Oliver Hartkopp | c7cd606 | 2009-12-12 04:13:21 +0000 | [diff] [blame] | 606 | cf->can_dlc = get_can_dlc((reg_msr >> 16) & 0xf); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 607 | |
Marc Kleine-Budde | e14ee40 | 2010-10-21 18:39:26 +0200 | [diff] [blame] | 608 | if (reg_msr & AT91_MSR_MRTR) |
| 609 | cf->can_id |= CAN_RTR_FLAG; |
| 610 | else { |
| 611 | *(u32 *)(cf->data + 0) = at91_read(priv, AT91_MDL(mb)); |
| 612 | *(u32 *)(cf->data + 4) = at91_read(priv, AT91_MDH(mb)); |
| 613 | } |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 614 | |
Marc Kleine-Budde | 8a0e0a4 | 2010-10-21 01:01:14 +0000 | [diff] [blame] | 615 | /* allow RX of extended frames */ |
| 616 | at91_write(priv, AT91_MID(mb), AT91_MID_MIDE); |
| 617 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 618 | if (unlikely(mb == get_mb_rx_last(priv) && reg_msr & AT91_MSR_MMI)) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 619 | at91_rx_overflow_err(dev); |
| 620 | } |
| 621 | |
| 622 | /** |
| 623 | * at91_read_msg - read CAN message from mailbox |
| 624 | * @dev: net device |
| 625 | * @mb: mail box to read from |
| 626 | * |
| 627 | * Reads a CAN message from given mailbox, and put into linux network |
| 628 | * RX queue, does all housekeeping chores (stats, ...) |
| 629 | */ |
| 630 | static void at91_read_msg(struct net_device *dev, unsigned int mb) |
| 631 | { |
| 632 | struct net_device_stats *stats = &dev->stats; |
| 633 | struct can_frame *cf; |
| 634 | struct sk_buff *skb; |
| 635 | |
| 636 | skb = alloc_can_skb(dev, &cf); |
| 637 | if (unlikely(!skb)) { |
| 638 | stats->rx_dropped++; |
| 639 | return; |
| 640 | } |
| 641 | |
| 642 | at91_read_mb(dev, mb, cf); |
| 643 | netif_receive_skb(skb); |
| 644 | |
| 645 | stats->rx_packets++; |
| 646 | stats->rx_bytes += cf->can_dlc; |
| 647 | } |
| 648 | |
| 649 | /** |
| 650 | * at91_poll_rx - read multiple CAN messages from mailboxes |
| 651 | * @dev: net device |
| 652 | * @quota: max number of pkgs we're allowed to receive |
| 653 | * |
| 654 | * Theory of Operation: |
| 655 | * |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 656 | * About 3/4 of the mailboxes (get_mb_rx_first()...get_mb_rx_last()) |
| 657 | * on the chip are reserved for RX. We split them into 2 groups. The |
| 658 | * lower group ranges from get_mb_rx_first() to get_mb_rx_low_last(). |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 659 | * |
| 660 | * Like it or not, but the chip always saves a received CAN message |
| 661 | * into the first free mailbox it finds (starting with the |
| 662 | * lowest). This makes it very difficult to read the messages in the |
| 663 | * right order from the chip. This is how we work around that problem: |
| 664 | * |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 665 | * The first message goes into mb nr. 1 and issues an interrupt. All |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 666 | * rx ints are disabled in the interrupt handler and a napi poll is |
| 667 | * scheduled. We read the mailbox, but do _not_ reenable the mb (to |
| 668 | * receive another message). |
| 669 | * |
| 670 | * lower mbxs upper |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 671 | * ____^______ __^__ |
| 672 | * / \ / \ |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 673 | * +-+-+-+-+-+-+-+-++-+-+-+-+ |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 674 | * | |x|x|x|x|x|x|x|| | | | | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 675 | * +-+-+-+-+-+-+-+-++-+-+-+-+ |
| 676 | * 0 0 0 0 0 0 0 0 0 0 1 1 \ mail |
| 677 | * 0 1 2 3 4 5 6 7 8 9 0 1 / box |
Marc Kleine-Budde | 9e0a2d1 | 2011-01-09 22:46:25 +0100 | [diff] [blame] | 678 | * ^ |
| 679 | * | |
| 680 | * \ |
| 681 | * unused, due to chip bug |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 682 | * |
| 683 | * The variable priv->rx_next points to the next mailbox to read a |
| 684 | * message from. As long we're in the lower mailboxes we just read the |
| 685 | * mailbox but not reenable it. |
| 686 | * |
| 687 | * With completion of the last of the lower mailboxes, we reenable the |
| 688 | * whole first group, but continue to look for filled mailboxes in the |
| 689 | * upper mailboxes. Imagine the second group like overflow mailboxes, |
| 690 | * which takes CAN messages if the lower goup is full. While in the |
| 691 | * upper group we reenable the mailbox right after reading it. Giving |
| 692 | * the chip more room to store messages. |
| 693 | * |
| 694 | * After finishing we look again in the lower group if we've still |
| 695 | * quota. |
| 696 | * |
| 697 | */ |
| 698 | static int at91_poll_rx(struct net_device *dev, int quota) |
| 699 | { |
| 700 | struct at91_priv *priv = netdev_priv(dev); |
| 701 | u32 reg_sr = at91_read(priv, AT91_SR); |
| 702 | const unsigned long *addr = (unsigned long *)®_sr; |
| 703 | unsigned int mb; |
| 704 | int received = 0; |
| 705 | |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 706 | if (priv->rx_next > get_mb_rx_low_last(priv) && |
| 707 | reg_sr & get_mb_rx_low_mask(priv)) |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 708 | netdev_info(dev, |
| 709 | "order of incoming frames cannot be guaranteed\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 710 | |
| 711 | again: |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 712 | for (mb = find_next_bit(addr, get_mb_tx_first(priv), priv->rx_next); |
| 713 | mb < get_mb_tx_first(priv) && quota > 0; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 714 | reg_sr = at91_read(priv, AT91_SR), |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 715 | mb = find_next_bit(addr, get_mb_tx_first(priv), ++priv->rx_next)) { |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 716 | at91_read_msg(dev, mb); |
| 717 | |
| 718 | /* reactivate mailboxes */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 719 | if (mb == get_mb_rx_low_last(priv)) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 720 | /* all lower mailboxed, if just finished it */ |
| 721 | at91_activate_rx_low(priv); |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 722 | else if (mb > get_mb_rx_low_last(priv)) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 723 | /* only the mailbox we read */ |
| 724 | at91_activate_rx_mb(priv, mb); |
| 725 | |
| 726 | received++; |
| 727 | quota--; |
| 728 | } |
| 729 | |
| 730 | /* upper group completed, look again in lower */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 731 | if (priv->rx_next > get_mb_rx_low_last(priv) && |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 732 | quota > 0 && mb > get_mb_rx_last(priv)) { |
| 733 | priv->rx_next = get_mb_rx_first(priv); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 734 | goto again; |
| 735 | } |
| 736 | |
| 737 | return received; |
| 738 | } |
| 739 | |
| 740 | static void at91_poll_err_frame(struct net_device *dev, |
| 741 | struct can_frame *cf, u32 reg_sr) |
| 742 | { |
| 743 | struct at91_priv *priv = netdev_priv(dev); |
| 744 | |
| 745 | /* CRC error */ |
| 746 | if (reg_sr & AT91_IRQ_CERR) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 747 | netdev_dbg(dev, "CERR irq\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 748 | dev->stats.rx_errors++; |
| 749 | priv->can.can_stats.bus_error++; |
| 750 | cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; |
| 751 | } |
| 752 | |
| 753 | /* Stuffing Error */ |
| 754 | if (reg_sr & AT91_IRQ_SERR) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 755 | netdev_dbg(dev, "SERR irq\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 756 | dev->stats.rx_errors++; |
| 757 | priv->can.can_stats.bus_error++; |
| 758 | cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; |
| 759 | cf->data[2] |= CAN_ERR_PROT_STUFF; |
| 760 | } |
| 761 | |
| 762 | /* Acknowledgement Error */ |
| 763 | if (reg_sr & AT91_IRQ_AERR) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 764 | netdev_dbg(dev, "AERR irq\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 765 | dev->stats.tx_errors++; |
| 766 | cf->can_id |= CAN_ERR_ACK; |
| 767 | } |
| 768 | |
| 769 | /* Form error */ |
| 770 | if (reg_sr & AT91_IRQ_FERR) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 771 | netdev_dbg(dev, "FERR irq\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 772 | dev->stats.rx_errors++; |
| 773 | priv->can.can_stats.bus_error++; |
| 774 | cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; |
| 775 | cf->data[2] |= CAN_ERR_PROT_FORM; |
| 776 | } |
| 777 | |
| 778 | /* Bit Error */ |
| 779 | if (reg_sr & AT91_IRQ_BERR) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 780 | netdev_dbg(dev, "BERR irq\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 781 | dev->stats.tx_errors++; |
| 782 | priv->can.can_stats.bus_error++; |
| 783 | cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; |
| 784 | cf->data[2] |= CAN_ERR_PROT_BIT; |
| 785 | } |
| 786 | } |
| 787 | |
| 788 | static int at91_poll_err(struct net_device *dev, int quota, u32 reg_sr) |
| 789 | { |
| 790 | struct sk_buff *skb; |
| 791 | struct can_frame *cf; |
| 792 | |
| 793 | if (quota == 0) |
| 794 | return 0; |
| 795 | |
| 796 | skb = alloc_can_err_skb(dev, &cf); |
| 797 | if (unlikely(!skb)) |
| 798 | return 0; |
| 799 | |
| 800 | at91_poll_err_frame(dev, cf, reg_sr); |
| 801 | netif_receive_skb(skb); |
| 802 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 803 | dev->stats.rx_packets++; |
| 804 | dev->stats.rx_bytes += cf->can_dlc; |
| 805 | |
| 806 | return 1; |
| 807 | } |
| 808 | |
| 809 | static int at91_poll(struct napi_struct *napi, int quota) |
| 810 | { |
| 811 | struct net_device *dev = napi->dev; |
| 812 | const struct at91_priv *priv = netdev_priv(dev); |
| 813 | u32 reg_sr = at91_read(priv, AT91_SR); |
| 814 | int work_done = 0; |
| 815 | |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 816 | if (reg_sr & get_irq_mb_rx(priv)) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 817 | work_done += at91_poll_rx(dev, quota - work_done); |
| 818 | |
| 819 | /* |
| 820 | * The error bits are clear on read, |
| 821 | * so use saved value from irq handler. |
| 822 | */ |
| 823 | reg_sr |= priv->reg_sr; |
| 824 | if (reg_sr & AT91_IRQ_ERR_FRAME) |
| 825 | work_done += at91_poll_err(dev, quota - work_done, reg_sr); |
| 826 | |
| 827 | if (work_done < quota) { |
| 828 | /* enable IRQs for frame errors and all mailboxes >= rx_next */ |
| 829 | u32 reg_ier = AT91_IRQ_ERR_FRAME; |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 830 | reg_ier |= get_irq_mb_rx(priv) & ~AT91_MB_MASK(priv->rx_next); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 831 | |
| 832 | napi_complete(napi); |
| 833 | at91_write(priv, AT91_IER, reg_ier); |
| 834 | } |
| 835 | |
| 836 | return work_done; |
| 837 | } |
| 838 | |
| 839 | /* |
| 840 | * theory of operation: |
| 841 | * |
| 842 | * priv->tx_echo holds the number of the oldest can_frame put for |
| 843 | * transmission into the hardware, but not yet ACKed by the CAN tx |
| 844 | * complete IRQ. |
| 845 | * |
| 846 | * We iterate from priv->tx_echo to priv->tx_next and check if the |
| 847 | * packet has been transmitted, echo it back to the CAN framework. If |
| 848 | * we discover a not yet transmitted package, stop looking for more. |
| 849 | * |
| 850 | */ |
| 851 | static void at91_irq_tx(struct net_device *dev, u32 reg_sr) |
| 852 | { |
| 853 | struct at91_priv *priv = netdev_priv(dev); |
| 854 | u32 reg_msr; |
| 855 | unsigned int mb; |
| 856 | |
| 857 | /* masking of reg_sr not needed, already done by at91_irq */ |
| 858 | |
| 859 | for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) { |
| 860 | mb = get_tx_echo_mb(priv); |
| 861 | |
| 862 | /* no event in mailbox? */ |
| 863 | if (!(reg_sr & (1 << mb))) |
| 864 | break; |
| 865 | |
| 866 | /* Disable irq for this TX mailbox */ |
| 867 | at91_write(priv, AT91_IDR, 1 << mb); |
| 868 | |
| 869 | /* |
| 870 | * only echo if mailbox signals us a transfer |
| 871 | * complete (MSR_MRDY). Otherwise it's a tansfer |
| 872 | * abort. "can_bus_off()" takes care about the skbs |
| 873 | * parked in the echo queue. |
| 874 | */ |
| 875 | reg_msr = at91_read(priv, AT91_MSR(mb)); |
| 876 | if (likely(reg_msr & AT91_MSR_MRDY && |
| 877 | ~reg_msr & AT91_MSR_MABT)) { |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 878 | /* _NOTE_: subtract AT91_MB_TX_FIRST offset from mb! */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 879 | can_get_echo_skb(dev, mb - get_mb_tx_first(priv)); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 880 | dev->stats.tx_packets++; |
| 881 | } |
| 882 | } |
| 883 | |
| 884 | /* |
| 885 | * restart queue if we don't have a wrap around but restart if |
| 886 | * we get a TX int for the last can frame directly before a |
| 887 | * wrap around. |
| 888 | */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 889 | if ((priv->tx_next & get_next_mask(priv)) != 0 || |
| 890 | (priv->tx_echo & get_next_mask(priv)) == 0) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 891 | netif_wake_queue(dev); |
| 892 | } |
| 893 | |
| 894 | static void at91_irq_err_state(struct net_device *dev, |
| 895 | struct can_frame *cf, enum can_state new_state) |
| 896 | { |
| 897 | struct at91_priv *priv = netdev_priv(dev); |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 898 | u32 reg_idr = 0, reg_ier = 0; |
| 899 | struct can_berr_counter bec; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 900 | |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 901 | at91_get_berr_counter(dev, &bec); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 902 | |
| 903 | switch (priv->can.state) { |
| 904 | case CAN_STATE_ERROR_ACTIVE: |
| 905 | /* |
| 906 | * from: ERROR_ACTIVE |
| 907 | * to : ERROR_WARNING, ERROR_PASSIVE, BUS_OFF |
| 908 | * => : there was a warning int |
| 909 | */ |
| 910 | if (new_state >= CAN_STATE_ERROR_WARNING && |
| 911 | new_state <= CAN_STATE_BUS_OFF) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 912 | netdev_dbg(dev, "Error Warning IRQ\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 913 | priv->can.can_stats.error_warning++; |
| 914 | |
| 915 | cf->can_id |= CAN_ERR_CRTL; |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 916 | cf->data[1] = (bec.txerr > bec.rxerr) ? |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 917 | CAN_ERR_CRTL_TX_WARNING : |
| 918 | CAN_ERR_CRTL_RX_WARNING; |
| 919 | } |
| 920 | case CAN_STATE_ERROR_WARNING: /* fallthrough */ |
| 921 | /* |
| 922 | * from: ERROR_ACTIVE, ERROR_WARNING |
| 923 | * to : ERROR_PASSIVE, BUS_OFF |
| 924 | * => : error passive int |
| 925 | */ |
| 926 | if (new_state >= CAN_STATE_ERROR_PASSIVE && |
| 927 | new_state <= CAN_STATE_BUS_OFF) { |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 928 | netdev_dbg(dev, "Error Passive IRQ\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 929 | priv->can.can_stats.error_passive++; |
| 930 | |
| 931 | cf->can_id |= CAN_ERR_CRTL; |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 932 | cf->data[1] = (bec.txerr > bec.rxerr) ? |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 933 | CAN_ERR_CRTL_TX_PASSIVE : |
| 934 | CAN_ERR_CRTL_RX_PASSIVE; |
| 935 | } |
| 936 | break; |
| 937 | case CAN_STATE_BUS_OFF: |
| 938 | /* |
| 939 | * from: BUS_OFF |
| 940 | * to : ERROR_ACTIVE, ERROR_WARNING, ERROR_PASSIVE |
| 941 | */ |
| 942 | if (new_state <= CAN_STATE_ERROR_PASSIVE) { |
| 943 | cf->can_id |= CAN_ERR_RESTARTED; |
| 944 | |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 945 | netdev_dbg(dev, "restarted\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 946 | priv->can.can_stats.restarts++; |
| 947 | |
| 948 | netif_carrier_on(dev); |
| 949 | netif_wake_queue(dev); |
| 950 | } |
| 951 | break; |
| 952 | default: |
| 953 | break; |
| 954 | } |
| 955 | |
| 956 | |
| 957 | /* process state changes depending on the new state */ |
| 958 | switch (new_state) { |
| 959 | case CAN_STATE_ERROR_ACTIVE: |
| 960 | /* |
| 961 | * actually we want to enable AT91_IRQ_WARN here, but |
| 962 | * it screws up the system under certain |
| 963 | * circumstances. so just enable AT91_IRQ_ERRP, thus |
| 964 | * the "fallthrough" |
| 965 | */ |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 966 | netdev_dbg(dev, "Error Active\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 967 | cf->can_id |= CAN_ERR_PROT; |
| 968 | cf->data[2] = CAN_ERR_PROT_ACTIVE; |
| 969 | case CAN_STATE_ERROR_WARNING: /* fallthrough */ |
| 970 | reg_idr = AT91_IRQ_ERRA | AT91_IRQ_WARN | AT91_IRQ_BOFF; |
| 971 | reg_ier = AT91_IRQ_ERRP; |
| 972 | break; |
| 973 | case CAN_STATE_ERROR_PASSIVE: |
| 974 | reg_idr = AT91_IRQ_ERRA | AT91_IRQ_WARN | AT91_IRQ_ERRP; |
| 975 | reg_ier = AT91_IRQ_BOFF; |
| 976 | break; |
| 977 | case CAN_STATE_BUS_OFF: |
| 978 | reg_idr = AT91_IRQ_ERRA | AT91_IRQ_ERRP | |
| 979 | AT91_IRQ_WARN | AT91_IRQ_BOFF; |
| 980 | reg_ier = 0; |
| 981 | |
| 982 | cf->can_id |= CAN_ERR_BUSOFF; |
| 983 | |
Marc Kleine-Budde | 882055c | 2010-10-21 01:01:21 +0000 | [diff] [blame] | 984 | netdev_dbg(dev, "bus-off\n"); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 985 | netif_carrier_off(dev); |
| 986 | priv->can.can_stats.bus_off++; |
| 987 | |
| 988 | /* turn off chip, if restart is disabled */ |
| 989 | if (!priv->can.restart_ms) { |
| 990 | at91_chip_stop(dev, CAN_STATE_BUS_OFF); |
| 991 | return; |
| 992 | } |
| 993 | break; |
| 994 | default: |
| 995 | break; |
| 996 | } |
| 997 | |
| 998 | at91_write(priv, AT91_IDR, reg_idr); |
| 999 | at91_write(priv, AT91_IER, reg_ier); |
| 1000 | } |
| 1001 | |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 1002 | static int at91_get_state_by_bec(const struct net_device *dev, |
| 1003 | enum can_state *state) |
| 1004 | { |
| 1005 | struct can_berr_counter bec; |
| 1006 | int err; |
| 1007 | |
| 1008 | err = at91_get_berr_counter(dev, &bec); |
| 1009 | if (err) |
| 1010 | return err; |
| 1011 | |
| 1012 | if (bec.txerr < 96 && bec.rxerr < 96) |
| 1013 | *state = CAN_STATE_ERROR_ACTIVE; |
| 1014 | else if (bec.txerr < 128 && bec.rxerr < 128) |
| 1015 | *state = CAN_STATE_ERROR_WARNING; |
| 1016 | else if (bec.txerr < 256 && bec.rxerr < 256) |
| 1017 | *state = CAN_STATE_ERROR_PASSIVE; |
| 1018 | else |
| 1019 | *state = CAN_STATE_BUS_OFF; |
| 1020 | |
| 1021 | return 0; |
| 1022 | } |
| 1023 | |
| 1024 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1025 | static void at91_irq_err(struct net_device *dev) |
| 1026 | { |
| 1027 | struct at91_priv *priv = netdev_priv(dev); |
| 1028 | struct sk_buff *skb; |
| 1029 | struct can_frame *cf; |
| 1030 | enum can_state new_state; |
| 1031 | u32 reg_sr; |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 1032 | int err; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1033 | |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 1034 | if (at91_is_sam9263(priv)) { |
| 1035 | reg_sr = at91_read(priv, AT91_SR); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1036 | |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 1037 | /* we need to look at the unmasked reg_sr */ |
| 1038 | if (unlikely(reg_sr & AT91_IRQ_BOFF)) |
| 1039 | new_state = CAN_STATE_BUS_OFF; |
| 1040 | else if (unlikely(reg_sr & AT91_IRQ_ERRP)) |
| 1041 | new_state = CAN_STATE_ERROR_PASSIVE; |
| 1042 | else if (unlikely(reg_sr & AT91_IRQ_WARN)) |
| 1043 | new_state = CAN_STATE_ERROR_WARNING; |
| 1044 | else if (likely(reg_sr & AT91_IRQ_ERRA)) |
| 1045 | new_state = CAN_STATE_ERROR_ACTIVE; |
| 1046 | else { |
| 1047 | netdev_err(dev, "BUG! hardware in undefined state\n"); |
| 1048 | return; |
| 1049 | } |
| 1050 | } else { |
| 1051 | err = at91_get_state_by_bec(dev, &new_state); |
| 1052 | if (err) |
| 1053 | return; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1054 | } |
| 1055 | |
| 1056 | /* state hasn't changed */ |
| 1057 | if (likely(new_state == priv->can.state)) |
| 1058 | return; |
| 1059 | |
| 1060 | skb = alloc_can_err_skb(dev, &cf); |
| 1061 | if (unlikely(!skb)) |
| 1062 | return; |
| 1063 | |
| 1064 | at91_irq_err_state(dev, cf, new_state); |
| 1065 | netif_rx(skb); |
| 1066 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1067 | dev->stats.rx_packets++; |
| 1068 | dev->stats.rx_bytes += cf->can_dlc; |
| 1069 | |
| 1070 | priv->can.state = new_state; |
| 1071 | } |
| 1072 | |
| 1073 | /* |
| 1074 | * interrupt handler |
| 1075 | */ |
| 1076 | static irqreturn_t at91_irq(int irq, void *dev_id) |
| 1077 | { |
| 1078 | struct net_device *dev = dev_id; |
| 1079 | struct at91_priv *priv = netdev_priv(dev); |
| 1080 | irqreturn_t handled = IRQ_NONE; |
| 1081 | u32 reg_sr, reg_imr; |
| 1082 | |
| 1083 | reg_sr = at91_read(priv, AT91_SR); |
| 1084 | reg_imr = at91_read(priv, AT91_IMR); |
| 1085 | |
| 1086 | /* Ignore masked interrupts */ |
| 1087 | reg_sr &= reg_imr; |
| 1088 | if (!reg_sr) |
| 1089 | goto exit; |
| 1090 | |
| 1091 | handled = IRQ_HANDLED; |
| 1092 | |
| 1093 | /* Receive or error interrupt? -> napi */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 1094 | if (reg_sr & (get_irq_mb_rx(priv) | AT91_IRQ_ERR_FRAME)) { |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1095 | /* |
| 1096 | * The error bits are clear on read, |
| 1097 | * save for later use. |
| 1098 | */ |
| 1099 | priv->reg_sr = reg_sr; |
| 1100 | at91_write(priv, AT91_IDR, |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 1101 | get_irq_mb_rx(priv) | AT91_IRQ_ERR_FRAME); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1102 | napi_schedule(&priv->napi); |
| 1103 | } |
| 1104 | |
| 1105 | /* Transmission complete interrupt */ |
Marc Kleine-Budde | 7900899 | 2011-05-03 17:31:40 +0200 | [diff] [blame] | 1106 | if (reg_sr & get_irq_mb_tx(priv)) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1107 | at91_irq_tx(dev, reg_sr); |
| 1108 | |
| 1109 | at91_irq_err(dev); |
| 1110 | |
| 1111 | exit: |
| 1112 | return handled; |
| 1113 | } |
| 1114 | |
| 1115 | static int at91_open(struct net_device *dev) |
| 1116 | { |
| 1117 | struct at91_priv *priv = netdev_priv(dev); |
| 1118 | int err; |
| 1119 | |
| 1120 | clk_enable(priv->clk); |
| 1121 | |
| 1122 | /* check or determine and set bittime */ |
| 1123 | err = open_candev(dev); |
| 1124 | if (err) |
| 1125 | goto out; |
| 1126 | |
| 1127 | /* register interrupt handler */ |
| 1128 | if (request_irq(dev->irq, at91_irq, IRQF_SHARED, |
| 1129 | dev->name, dev)) { |
| 1130 | err = -EAGAIN; |
| 1131 | goto out_close; |
| 1132 | } |
| 1133 | |
| 1134 | /* start chip and queuing */ |
| 1135 | at91_chip_start(dev); |
| 1136 | napi_enable(&priv->napi); |
| 1137 | netif_start_queue(dev); |
| 1138 | |
| 1139 | return 0; |
| 1140 | |
| 1141 | out_close: |
| 1142 | close_candev(dev); |
| 1143 | out: |
| 1144 | clk_disable(priv->clk); |
| 1145 | |
| 1146 | return err; |
| 1147 | } |
| 1148 | |
| 1149 | /* |
| 1150 | * stop CAN bus activity |
| 1151 | */ |
| 1152 | static int at91_close(struct net_device *dev) |
| 1153 | { |
| 1154 | struct at91_priv *priv = netdev_priv(dev); |
| 1155 | |
| 1156 | netif_stop_queue(dev); |
| 1157 | napi_disable(&priv->napi); |
| 1158 | at91_chip_stop(dev, CAN_STATE_STOPPED); |
| 1159 | |
| 1160 | free_irq(dev->irq, dev); |
| 1161 | clk_disable(priv->clk); |
| 1162 | |
| 1163 | close_candev(dev); |
| 1164 | |
| 1165 | return 0; |
| 1166 | } |
| 1167 | |
| 1168 | static int at91_set_mode(struct net_device *dev, enum can_mode mode) |
| 1169 | { |
| 1170 | switch (mode) { |
| 1171 | case CAN_MODE_START: |
| 1172 | at91_chip_start(dev); |
| 1173 | netif_wake_queue(dev); |
| 1174 | break; |
| 1175 | |
| 1176 | default: |
| 1177 | return -EOPNOTSUPP; |
| 1178 | } |
| 1179 | |
| 1180 | return 0; |
| 1181 | } |
| 1182 | |
| 1183 | static const struct net_device_ops at91_netdev_ops = { |
| 1184 | .ndo_open = at91_open, |
| 1185 | .ndo_stop = at91_close, |
| 1186 | .ndo_start_xmit = at91_start_xmit, |
| 1187 | }; |
| 1188 | |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 1189 | static ssize_t at91_sysfs_show_mb0_id(struct device *dev, |
| 1190 | struct device_attribute *attr, char *buf) |
| 1191 | { |
| 1192 | struct at91_priv *priv = netdev_priv(to_net_dev(dev)); |
| 1193 | |
| 1194 | if (priv->mb0_id & CAN_EFF_FLAG) |
| 1195 | return snprintf(buf, PAGE_SIZE, "0x%08x\n", priv->mb0_id); |
| 1196 | else |
| 1197 | return snprintf(buf, PAGE_SIZE, "0x%03x\n", priv->mb0_id); |
| 1198 | } |
| 1199 | |
| 1200 | static ssize_t at91_sysfs_set_mb0_id(struct device *dev, |
| 1201 | struct device_attribute *attr, const char *buf, size_t count) |
| 1202 | { |
| 1203 | struct net_device *ndev = to_net_dev(dev); |
| 1204 | struct at91_priv *priv = netdev_priv(ndev); |
| 1205 | unsigned long can_id; |
| 1206 | ssize_t ret; |
| 1207 | int err; |
| 1208 | |
| 1209 | rtnl_lock(); |
| 1210 | |
| 1211 | if (ndev->flags & IFF_UP) { |
| 1212 | ret = -EBUSY; |
| 1213 | goto out; |
| 1214 | } |
| 1215 | |
| 1216 | err = strict_strtoul(buf, 0, &can_id); |
| 1217 | if (err) { |
| 1218 | ret = err; |
| 1219 | goto out; |
| 1220 | } |
| 1221 | |
| 1222 | if (can_id & CAN_EFF_FLAG) |
| 1223 | can_id &= CAN_EFF_MASK | CAN_EFF_FLAG; |
| 1224 | else |
| 1225 | can_id &= CAN_SFF_MASK; |
| 1226 | |
| 1227 | priv->mb0_id = can_id; |
| 1228 | ret = count; |
| 1229 | |
| 1230 | out: |
| 1231 | rtnl_unlock(); |
| 1232 | return ret; |
| 1233 | } |
| 1234 | |
Vasiliy Kulikov | fef52b0 | 2011-02-04 02:23:50 +0000 | [diff] [blame] | 1235 | static DEVICE_ATTR(mb0_id, S_IWUSR | S_IRUGO, |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 1236 | at91_sysfs_show_mb0_id, at91_sysfs_set_mb0_id); |
| 1237 | |
| 1238 | static struct attribute *at91_sysfs_attrs[] = { |
| 1239 | &dev_attr_mb0_id.attr, |
| 1240 | NULL, |
| 1241 | }; |
| 1242 | |
| 1243 | static struct attribute_group at91_sysfs_attr_group = { |
| 1244 | .attrs = at91_sysfs_attrs, |
| 1245 | }; |
| 1246 | |
Marc Kleine-Budde | a9d992e | 2010-10-21 01:01:17 +0000 | [diff] [blame] | 1247 | static int __devinit at91_can_probe(struct platform_device *pdev) |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1248 | { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1249 | const struct at91_devtype_data *devtype_data; |
| 1250 | enum at91_devtype devtype; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1251 | struct net_device *dev; |
| 1252 | struct at91_priv *priv; |
| 1253 | struct resource *res; |
| 1254 | struct clk *clk; |
| 1255 | void __iomem *addr; |
| 1256 | int err, irq; |
| 1257 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1258 | devtype = pdev->id_entry->driver_data; |
| 1259 | devtype_data = &at91_devtype_data[devtype]; |
| 1260 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1261 | clk = clk_get(&pdev->dev, "can_clk"); |
| 1262 | if (IS_ERR(clk)) { |
| 1263 | dev_err(&pdev->dev, "no clock defined\n"); |
| 1264 | err = -ENODEV; |
| 1265 | goto exit; |
| 1266 | } |
| 1267 | |
| 1268 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 1269 | irq = platform_get_irq(pdev, 0); |
Uwe Kleine-König | 4773a47 | 2009-12-18 20:31:56 -0800 | [diff] [blame] | 1270 | if (!res || irq <= 0) { |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1271 | err = -ENODEV; |
| 1272 | goto exit_put; |
| 1273 | } |
| 1274 | |
| 1275 | if (!request_mem_region(res->start, |
| 1276 | resource_size(res), |
| 1277 | pdev->name)) { |
| 1278 | err = -EBUSY; |
| 1279 | goto exit_put; |
| 1280 | } |
| 1281 | |
| 1282 | addr = ioremap_nocache(res->start, resource_size(res)); |
| 1283 | if (!addr) { |
| 1284 | err = -ENOMEM; |
| 1285 | goto exit_release; |
| 1286 | } |
| 1287 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1288 | dev = alloc_candev(sizeof(struct at91_priv), |
| 1289 | 1 << devtype_data->tx_shift); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1290 | if (!dev) { |
| 1291 | err = -ENOMEM; |
| 1292 | goto exit_iounmap; |
| 1293 | } |
| 1294 | |
| 1295 | dev->netdev_ops = &at91_netdev_ops; |
| 1296 | dev->irq = irq; |
| 1297 | dev->flags |= IFF_ECHO; |
| 1298 | |
| 1299 | priv = netdev_priv(dev); |
| 1300 | priv->can.clock.freq = clk_get_rate(clk); |
| 1301 | priv->can.bittiming_const = &at91_bittiming_const; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1302 | priv->can.do_set_mode = at91_set_mode; |
Marc Kleine-Budde | 33a6f29 | 2010-10-21 01:01:18 +0000 | [diff] [blame] | 1303 | priv->can.do_get_berr_counter = at91_get_berr_counter; |
Christian Pellegrin | ad72c34 | 2010-01-14 07:08:34 +0000 | [diff] [blame] | 1304 | priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1305 | priv->dev = dev; |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1306 | priv->reg_base = addr; |
| 1307 | priv->devtype_data = *devtype_data; |
| 1308 | priv->devtype_data.type = devtype; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1309 | priv->clk = clk; |
| 1310 | priv->pdata = pdev->dev.platform_data; |
Marc Kleine-Budde | 3a5655a | 2011-01-10 20:44:22 +0100 | [diff] [blame] | 1311 | priv->mb0_id = 0x7ff; |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1312 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1313 | netif_napi_add(dev, &priv->napi, at91_poll, get_mb_rx_num(priv)); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1314 | |
Marc Kleine-Budde | 07a648e | 2011-06-01 00:20:17 +0200 | [diff] [blame] | 1315 | if (at91_is_sam9263(priv)) |
| 1316 | dev->sysfs_groups[0] = &at91_sysfs_attr_group; |
| 1317 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1318 | dev_set_drvdata(&pdev->dev, dev); |
| 1319 | SET_NETDEV_DEV(dev, &pdev->dev); |
| 1320 | |
| 1321 | err = register_candev(dev); |
| 1322 | if (err) { |
| 1323 | dev_err(&pdev->dev, "registering netdev failed\n"); |
| 1324 | goto exit_free; |
| 1325 | } |
| 1326 | |
| 1327 | dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n", |
| 1328 | priv->reg_base, dev->irq); |
| 1329 | |
| 1330 | return 0; |
| 1331 | |
| 1332 | exit_free: |
Marc Kleine-Budde | 759a6c7 | 2010-10-21 01:01:15 +0000 | [diff] [blame] | 1333 | free_candev(dev); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1334 | exit_iounmap: |
| 1335 | iounmap(addr); |
| 1336 | exit_release: |
| 1337 | release_mem_region(res->start, resource_size(res)); |
| 1338 | exit_put: |
| 1339 | clk_put(clk); |
| 1340 | exit: |
| 1341 | return err; |
| 1342 | } |
| 1343 | |
| 1344 | static int __devexit at91_can_remove(struct platform_device *pdev) |
| 1345 | { |
| 1346 | struct net_device *dev = platform_get_drvdata(pdev); |
| 1347 | struct at91_priv *priv = netdev_priv(dev); |
| 1348 | struct resource *res; |
| 1349 | |
| 1350 | unregister_netdev(dev); |
| 1351 | |
| 1352 | platform_set_drvdata(pdev, NULL); |
| 1353 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1354 | iounmap(priv->reg_base); |
| 1355 | |
| 1356 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 1357 | release_mem_region(res->start, resource_size(res)); |
| 1358 | |
| 1359 | clk_put(priv->clk); |
| 1360 | |
Marc Kleine-Budde | 759a6c7 | 2010-10-21 01:01:15 +0000 | [diff] [blame] | 1361 | free_candev(dev); |
| 1362 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1363 | return 0; |
| 1364 | } |
| 1365 | |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1366 | static const struct platform_device_id at91_can_id_table[] = { |
| 1367 | { |
| 1368 | .name = "at91_can", |
| 1369 | .driver_data = AT91_DEVTYPE_SAM9263, |
| 1370 | }, { |
Marc Kleine-Budde | 6388b39 | 2011-04-17 00:08:45 +0200 | [diff] [blame] | 1371 | .name = "at91sam9x5_can", |
| 1372 | .driver_data = AT91_DEVTYPE_SAM9X5, |
| 1373 | }, { |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1374 | /* sentinel */ |
| 1375 | } |
| 1376 | }; |
| 1377 | |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1378 | static struct platform_driver at91_can_driver = { |
Marc Kleine-Budde | 44d8566 | 2011-01-30 22:14:49 +0100 | [diff] [blame] | 1379 | .probe = at91_can_probe, |
| 1380 | .remove = __devexit_p(at91_can_remove), |
| 1381 | .driver = { |
| 1382 | .name = KBUILD_MODNAME, |
| 1383 | .owner = THIS_MODULE, |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1384 | }, |
Marc Kleine-Budde | d3d4726 | 2011-05-03 17:41:09 +0200 | [diff] [blame] | 1385 | .id_table = at91_can_id_table, |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1386 | }; |
| 1387 | |
| 1388 | static int __init at91_can_module_init(void) |
| 1389 | { |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1390 | return platform_driver_register(&at91_can_driver); |
| 1391 | } |
| 1392 | |
| 1393 | static void __exit at91_can_module_exit(void) |
| 1394 | { |
| 1395 | platform_driver_unregister(&at91_can_driver); |
David S. Miller | 99c4a63 | 2009-09-25 12:14:43 -0700 | [diff] [blame] | 1396 | } |
| 1397 | |
| 1398 | module_init(at91_can_module_init); |
| 1399 | module_exit(at91_can_module_exit); |
| 1400 | |
| 1401 | MODULE_AUTHOR("Marc Kleine-Budde <mkl@pengutronix.de>"); |
| 1402 | MODULE_LICENSE("GPL v2"); |
Marc Kleine-Budde | 00389b0 | 2010-10-21 01:01:22 +0000 | [diff] [blame] | 1403 | MODULE_DESCRIPTION(KBUILD_MODNAME " CAN netdevice driver"); |