diff options
author | Jon Ringle <jringle@gridpoint.com> | 2015-10-06 20:37:46 (GMT) |
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committer | David S. Miller <davem@davemloft.net> | 2015-10-08 11:49:55 (GMT) |
commit | d70e53262f5cfc0b88a211ef9cbd1ca5256f4a6b (patch) | |
tree | f617ca5dba505ee3b84d5bde7b1a7ad3cfcf6892 /drivers/net/ethernet/microchip/encx24j600-regmap.c | |
parent | 494f8eb9b616590c78bb1974aed835a842f012b6 (diff) | |
download | linux-d70e53262f5cfc0b88a211ef9cbd1ca5256f4a6b.tar.xz |
net: Microchip encx24j600 driver
This ethernet driver supports the Micorchip enc424j600/626j600 Ethernet
controller over a SPI bus interface. This driver makes use of the regmap API to
optimize access to registers by caching registers where possible.
Datasheet:
http://ww1.microchip.com/downloads/en/DeviceDoc/39935b.pdf
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/microchip/encx24j600-regmap.c')
-rw-r--r-- | drivers/net/ethernet/microchip/encx24j600-regmap.c | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/drivers/net/ethernet/microchip/encx24j600-regmap.c b/drivers/net/ethernet/microchip/encx24j600-regmap.c new file mode 100644 index 0000000..f3bb905 --- /dev/null +++ b/drivers/net/ethernet/microchip/encx24j600-regmap.c @@ -0,0 +1,513 @@ +/** + * Register map access API - ENCX24J600 support + * + * Copyright 2015 Gridpoint + * + * Author: Jon Ringle <jringle@gridpoint.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#include "encx24j600_hw.h" + +static inline bool is_bits_set(int value, int mask) +{ + return (value & mask) == mask; +} + +static int encx24j600_switch_bank(struct encx24j600_context *ctx, + int bank) +{ + int ret = 0; + + int bank_opcode = BANK_SELECT(bank); + ret = spi_write(ctx->spi, &bank_opcode, 1); + if (ret == 0) + ctx->bank = bank; + + return ret; +} + +static int encx24j600_cmdn(struct encx24j600_context *ctx, u8 opcode, + const void *buf, size_t len) +{ + struct spi_message m; + struct spi_transfer t[2] = { { .tx_buf = &opcode, .len = 1, }, + { .tx_buf = buf, .len = len }, }; + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + + return spi_sync(ctx->spi, &m); +} + +static void regmap_lock_mutex(void *context) +{ + struct encx24j600_context *ctx = context; + mutex_lock(&ctx->mutex); +} + +static void regmap_unlock_mutex(void *context) +{ + struct encx24j600_context *ctx = context; + mutex_unlock(&ctx->mutex); +} + +static int regmap_encx24j600_sfr_read(void *context, u8 reg, u8 *val, + size_t len) +{ + struct encx24j600_context *ctx = context; + u8 banked_reg = reg & ADDR_MASK; + u8 bank = ((reg & BANK_MASK) >> BANK_SHIFT); + u8 cmd = RCRU; + int ret = 0; + int i = 0; + u8 tx_buf[2]; + + if (reg < 0x80) { + cmd = RCRCODE | banked_reg; + if ((banked_reg < 0x16) && (ctx->bank != bank)) + ret = encx24j600_switch_bank(ctx, bank); + if (unlikely(ret)) + return ret; + } else { + /* Translate registers that are more effecient using + * 3-byte SPI commands + */ + switch (reg) { + case EGPRDPT: + cmd = RGPRDPT; break; + case EGPWRPT: + cmd = RGPWRPT; break; + case ERXRDPT: + cmd = RRXRDPT; break; + case ERXWRPT: + cmd = RRXWRPT; break; + case EUDARDPT: + cmd = RUDARDPT; break; + case EUDAWRPT: + cmd = RUDAWRPT; break; + case EGPDATA: + case ERXDATA: + case EUDADATA: + default: + return -EINVAL; + } + } + + tx_buf[i++] = cmd; + if (cmd == RCRU) + tx_buf[i++] = reg; + + ret = spi_write_then_read(ctx->spi, tx_buf, i, val, len); + + return ret; +} + +static int regmap_encx24j600_sfr_update(struct encx24j600_context *ctx, + u8 reg, u8 *val, size_t len, + u8 unbanked_cmd, u8 banked_code) +{ + u8 banked_reg = reg & ADDR_MASK; + u8 bank = ((reg & BANK_MASK) >> BANK_SHIFT); + u8 cmd = unbanked_cmd; + struct spi_message m; + struct spi_transfer t[3] = { { .tx_buf = &cmd, .len = sizeof(cmd), }, + { .tx_buf = ®, .len = sizeof(reg), }, + { .tx_buf = val, .len = len }, }; + + if (reg < 0x80) { + int ret = 0; + cmd = banked_code | banked_reg; + if ((banked_reg < 0x16) && (ctx->bank != bank)) + ret = encx24j600_switch_bank(ctx, bank); + if (unlikely(ret)) + return ret; + } else { + /* Translate registers that are more effecient using + * 3-byte SPI commands + */ + switch (reg) { + case EGPRDPT: + cmd = WGPRDPT; break; + case EGPWRPT: + cmd = WGPWRPT; break; + case ERXRDPT: + cmd = WRXRDPT; break; + case ERXWRPT: + cmd = WRXWRPT; break; + case EUDARDPT: + cmd = WUDARDPT; break; + case EUDAWRPT: + cmd = WUDAWRPT; break; + case EGPDATA: + case ERXDATA: + case EUDADATA: + default: + return -EINVAL; + } + } + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + + if (cmd == unbanked_cmd) { + t[1].tx_buf = ® + spi_message_add_tail(&t[1], &m); + } + + spi_message_add_tail(&t[2], &m); + return spi_sync(ctx->spi, &m); +} + +static int regmap_encx24j600_sfr_write(void *context, u8 reg, u8 *val, + size_t len) +{ + struct encx24j600_context *ctx = context; + return regmap_encx24j600_sfr_update(ctx, reg, val, len, WCRU, WCRCODE); +} + +static int regmap_encx24j600_sfr_set_bits(struct encx24j600_context *ctx, + u8 reg, u8 val) +{ + return regmap_encx24j600_sfr_update(ctx, reg, &val, 1, BFSU, BFSCODE); +} + +static int regmap_encx24j600_sfr_clr_bits(struct encx24j600_context *ctx, + u8 reg, u8 val) +{ + return regmap_encx24j600_sfr_update(ctx, reg, &val, 1, BFCU, BFCCODE); +} + +static int regmap_encx24j600_reg_update_bits(void *context, unsigned int reg, + unsigned int mask, + unsigned int val) +{ + struct encx24j600_context *ctx = context; + + int ret = 0; + unsigned int set_mask = mask & val; + unsigned int clr_mask = mask & ~val; + + if ((reg >= 0x40 && reg < 0x6c) || reg >= 0x80) + return -EINVAL; + + if (set_mask & 0xff) + ret = regmap_encx24j600_sfr_set_bits(ctx, reg, set_mask); + + set_mask = (set_mask & 0xff00) >> 8; + + if ((set_mask & 0xff) && (ret == 0)) + ret = regmap_encx24j600_sfr_set_bits(ctx, reg + 1, set_mask); + + if ((clr_mask & 0xff) && (ret == 0)) + ret = regmap_encx24j600_sfr_clr_bits(ctx, reg, clr_mask); + + clr_mask = (clr_mask & 0xff00) >> 8; + + if ((clr_mask & 0xff) && (ret == 0)) + ret = regmap_encx24j600_sfr_clr_bits(ctx, reg + 1, clr_mask); + + return ret; +} + +int regmap_encx24j600_spi_write(void *context, u8 reg, const u8 *data, + size_t count) +{ + struct encx24j600_context *ctx = context; + + if (reg < 0xc0) + return encx24j600_cmdn(ctx, reg, data, count); + else + /* SPI 1-byte command. Ignore data */ + return spi_write(ctx->spi, ®, 1); +} +EXPORT_SYMBOL_GPL(regmap_encx24j600_spi_write); + +int regmap_encx24j600_spi_read(void *context, u8 reg, u8 *data, size_t count) +{ + struct encx24j600_context *ctx = context; + + if (reg == RBSEL && count > 1) + count = 1; + + return spi_write_then_read(ctx->spi, ®, sizeof(reg), data, count); +} +EXPORT_SYMBOL_GPL(regmap_encx24j600_spi_read); + +static int regmap_encx24j600_write(void *context, const void *data, + size_t len) +{ + u8 *dout = (u8 *)data; + u8 reg = dout[0]; + ++dout; + --len; + + if (reg > 0xa0) + return regmap_encx24j600_spi_write(context, reg, dout, len); + + if (len > 2) + return -EINVAL; + + return regmap_encx24j600_sfr_write(context, reg, dout, len); +} + +static int regmap_encx24j600_read(void *context, + const void *reg_buf, size_t reg_size, + void *val, size_t val_size) +{ + u8 reg = *(const u8 *)reg_buf; + + if (reg_size != 1) { + pr_err("%s: reg=%02x reg_size=%zu\n", __func__, reg, reg_size); + return -EINVAL; + } + + if (reg > 0xa0) + return regmap_encx24j600_spi_read(context, reg, val, val_size); + + if (val_size > 2) { + pr_err("%s: reg=%02x val_size=%zu\n", __func__, reg, val_size); + return -EINVAL; + } + + return regmap_encx24j600_sfr_read(context, reg, val, val_size); +} + +static bool encx24j600_regmap_readable(struct device *dev, unsigned int reg) +{ + if ((reg < 0x36) || + ((reg >= 0x40) && (reg < 0x4c)) || + ((reg >= 0x52) && (reg < 0x56)) || + ((reg >= 0x60) && (reg < 0x66)) || + ((reg >= 0x68) && (reg < 0x80)) || + ((reg >= 0x86) && (reg < 0x92)) || + (reg == 0xc8)) + return true; + else + return false; +} + +static bool encx24j600_regmap_writeable(struct device *dev, unsigned int reg) +{ + if ((reg < 0x12) || + ((reg >= 0x14) && (reg < 0x1a)) || + ((reg >= 0x1c) && (reg < 0x36)) || + ((reg >= 0x40) && (reg < 0x4c)) || + ((reg >= 0x52) && (reg < 0x56)) || + ((reg >= 0x60) && (reg < 0x68)) || + ((reg >= 0x6c) && (reg < 0x80)) || + ((reg >= 0x86) && (reg < 0x92)) || + ((reg >= 0xc0) && (reg < 0xc8)) || + ((reg >= 0xca) && (reg < 0xf0))) + return true; + else + return false; +} + +static bool encx24j600_regmap_volatile(struct device *dev, unsigned int reg) +{ + switch (reg) { + case ERXHEAD: + case EDMACS: + case ETXSTAT: + case ETXWIRE: + case ECON1: /* Can be modified via single byte cmds */ + case ECON2: /* Can be modified via single byte cmds */ + case ESTAT: + case EIR: /* Can be modified via single byte cmds */ + case MIRD: + case MISTAT: + return true; + default: + break; + } + + return false; +} + +static bool encx24j600_regmap_precious(struct device *dev, unsigned int reg) +{ + /* single byte cmds are precious */ + if (((reg >= 0xc0) && (reg < 0xc8)) || + ((reg >= 0xca) && (reg < 0xf0))) + return true; + else + return false; +} + +static int regmap_encx24j600_phy_reg_read(void *context, unsigned int reg, + unsigned int *val) +{ + struct encx24j600_context *ctx = context; + int ret; + unsigned int mistat; + + reg = MIREGADR_VAL | (reg & PHREG_MASK); + ret = regmap_write(ctx->regmap, MIREGADR, reg); + if (unlikely(ret)) + goto err_out; + + ret = regmap_write(ctx->regmap, MICMD, MIIRD); + if (unlikely(ret)) + goto err_out; + + usleep_range(26, 100); + while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) && + (mistat & BUSY)) + cpu_relax(); + + if (unlikely(ret)) + goto err_out; + + ret = regmap_write(ctx->regmap, MICMD, 0); + if (unlikely(ret)) + goto err_out; + + ret = regmap_read(ctx->regmap, MIRD, val); + +err_out: + if (ret) + pr_err("%s: error %d reading reg %02x\n", __func__, ret, + reg & PHREG_MASK); + + return ret; +} + +static int regmap_encx24j600_phy_reg_write(void *context, unsigned int reg, + unsigned int val) +{ + struct encx24j600_context *ctx = context; + int ret; + unsigned int mistat; + + reg = MIREGADR_VAL | (reg & PHREG_MASK); + ret = regmap_write(ctx->regmap, MIREGADR, reg); + if (unlikely(ret)) + goto err_out; + + ret = regmap_write(ctx->regmap, MIWR, val); + if (unlikely(ret)) + goto err_out; + + usleep_range(26, 100); + while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) && + (mistat & BUSY)) + cpu_relax(); + +err_out: + if (ret) + pr_err("%s: error %d writing reg %02x=%04x\n", __func__, ret, + reg & PHREG_MASK, val); + + return ret; +} + +static bool encx24j600_phymap_readable(struct device *dev, unsigned int reg) +{ + switch (reg) { + case PHCON1: + case PHSTAT1: + case PHANA: + case PHANLPA: + case PHANE: + case PHCON2: + case PHSTAT2: + case PHSTAT3: + return true; + default: + return false; + } +} + +static bool encx24j600_phymap_writeable(struct device *dev, unsigned int reg) +{ + switch (reg) { + case PHCON1: + case PHCON2: + case PHANA: + return true; + case PHSTAT1: + case PHSTAT2: + case PHSTAT3: + case PHANLPA: + case PHANE: + default: + return false; + } +} + +static bool encx24j600_phymap_volatile(struct device *dev, unsigned int reg) +{ + switch (reg) { + case PHSTAT1: + case PHSTAT2: + case PHSTAT3: + case PHANLPA: + case PHANE: + case PHCON2: + return true; + default: + return false; + } +} + +static struct regmap_config regcfg = { + .name = "reg", + .reg_bits = 8, + .val_bits = 16, + .max_register = 0xee, + .reg_stride = 2, + .cache_type = REGCACHE_RBTREE, + .val_format_endian = REGMAP_ENDIAN_LITTLE, + .readable_reg = encx24j600_regmap_readable, + .writeable_reg = encx24j600_regmap_writeable, + .volatile_reg = encx24j600_regmap_volatile, + .precious_reg = encx24j600_regmap_precious, + .lock = regmap_lock_mutex, + .unlock = regmap_unlock_mutex, +}; + +static struct regmap_bus regmap_encx24j600 = { + .write = regmap_encx24j600_write, + .read = regmap_encx24j600_read, + .reg_update_bits = regmap_encx24j600_reg_update_bits, +}; + +static struct regmap_config phycfg = { + .name = "phy", + .reg_bits = 8, + .val_bits = 16, + .max_register = 0x1f, + .cache_type = REGCACHE_RBTREE, + .val_format_endian = REGMAP_ENDIAN_LITTLE, + .readable_reg = encx24j600_phymap_readable, + .writeable_reg = encx24j600_phymap_writeable, + .volatile_reg = encx24j600_phymap_volatile, +}; +static struct regmap_bus phymap_encx24j600 = { + .reg_write = regmap_encx24j600_phy_reg_write, + .reg_read = regmap_encx24j600_phy_reg_read, +}; + +void devm_regmap_init_encx24j600(struct device *dev, + struct encx24j600_context *ctx) +{ + mutex_init(&ctx->mutex); + regcfg.lock_arg = ctx; + ctx->regmap = devm_regmap_init(dev, ®map_encx24j600, ctx, ®cfg); + ctx->phymap = devm_regmap_init(dev, &phymap_encx24j600, ctx, &phycfg); +} +EXPORT_SYMBOL_GPL(devm_regmap_init_encx24j600); + +MODULE_LICENSE("GPL"); |