diff options
Diffstat (limited to 'drivers/net/phy/spi_ks8995.c')
| -rw-r--r-- | drivers/net/phy/spi_ks8995.c | 304 |
1 files changed, 245 insertions, 59 deletions
diff --git a/drivers/net/phy/spi_ks8995.c b/drivers/net/phy/spi_ks8995.c index c72c42206850..b5d50d458728 100644 --- a/drivers/net/phy/spi_ks8995.c +++ b/drivers/net/phy/spi_ks8995.c @@ -18,6 +18,9 @@ #include <linux/module.h> #include <linux/delay.h> #include <linux/device.h> +#include <linux/gpio/consumer.h> +#include <linux/of.h> +#include <linux/of_gpio.h> #include <linux/spi/spi.h> @@ -74,6 +77,7 @@ #define KS8995_REGS_SIZE 0x80 #define KSZ8864_REGS_SIZE 0x100 +#define KSZ8795_REGS_SIZE 0x100 #define ID1_CHIPID_M 0xf #define ID1_CHIPID_S 4 @@ -82,15 +86,63 @@ #define ID1_START_SW 1 /* start the switch */ #define FAMILY_KS8995 0x95 +#define FAMILY_KSZ8795 0x87 #define CHIPID_M 0 +#define KS8995_CHIP_ID 0x00 +#define KSZ8864_CHIP_ID 0x01 +#define KSZ8795_CHIP_ID 0x09 #define KS8995_CMD_WRITE 0x02U #define KS8995_CMD_READ 0x03U #define KS8995_RESET_DELAY 10 /* usec */ +enum ks8995_chip_variant { + ks8995, + ksz8864, + ksz8795, + max_variant +}; + +struct ks8995_chip_params { + char *name; + int family_id; + int chip_id; + int regs_size; + int addr_width; + int addr_shift; +}; + +static const struct ks8995_chip_params ks8995_chip[] = { + [ks8995] = { + .name = "KS8995MA", + .family_id = FAMILY_KS8995, + .chip_id = KS8995_CHIP_ID, + .regs_size = KS8995_REGS_SIZE, + .addr_width = 8, + .addr_shift = 0, + }, + [ksz8864] = { + .name = "KSZ8864RMN", + .family_id = FAMILY_KS8995, + .chip_id = KSZ8864_CHIP_ID, + .regs_size = KSZ8864_REGS_SIZE, + .addr_width = 8, + .addr_shift = 0, + }, + [ksz8795] = { + .name = "KSZ8795CLX", + .family_id = FAMILY_KSZ8795, + .chip_id = KSZ8795_CHIP_ID, + .regs_size = KSZ8795_REGS_SIZE, + .addr_width = 12, + .addr_shift = 1, + }, +}; + struct ks8995_pdata { - /* not yet implemented */ + int reset_gpio; + enum of_gpio_flags reset_gpio_flags; }; struct ks8995_switch { @@ -98,7 +150,17 @@ struct ks8995_switch { struct mutex lock; struct ks8995_pdata *pdata; struct bin_attribute regs_attr; + const struct ks8995_chip_params *chip; + int revision_id; +}; + +static const struct spi_device_id ks8995_id[] = { + {"ks8995", ks8995}, + {"ksz8864", ksz8864}, + {"ksz8795", ksz8795}, + { } }; +MODULE_DEVICE_TABLE(spi, ks8995_id); static inline u8 get_chip_id(u8 val) { @@ -110,20 +172,44 @@ static inline u8 get_chip_rev(u8 val) return (val >> ID1_REVISION_S) & ID1_REVISION_M; } +/* create_spi_cmd - create a chip specific SPI command header + * @ks: pointer to switch instance + * @cmd: SPI command for switch + * @address: register address for command + * + * Different chip families use different bit pattern to address the switches + * registers: + * + * KS8995: 8bit command + 8bit address + * KSZ8795: 3bit command + 12bit address + 1bit TR (?) + */ +static inline __be16 create_spi_cmd(struct ks8995_switch *ks, int cmd, + unsigned address) +{ + u16 result = cmd; + + /* make room for address (incl. address shift) */ + result <<= ks->chip->addr_width + ks->chip->addr_shift; + /* add address */ + result |= address << ks->chip->addr_shift; + /* SPI protocol needs big endian */ + return cpu_to_be16(result); +} /* ------------------------------------------------------------------------ */ static int ks8995_read(struct ks8995_switch *ks, char *buf, unsigned offset, size_t count) { - u8 cmd[2]; + __be16 cmd; struct spi_transfer t[2]; struct spi_message m; int err; + cmd = create_spi_cmd(ks, KS8995_CMD_READ, offset); spi_message_init(&m); memset(&t, 0, sizeof(t)); - t[0].tx_buf = cmd; + t[0].tx_buf = &cmd; t[0].len = sizeof(cmd); spi_message_add_tail(&t[0], &m); @@ -131,9 +217,6 @@ static int ks8995_read(struct ks8995_switch *ks, char *buf, t[1].len = count; spi_message_add_tail(&t[1], &m); - cmd[0] = KS8995_CMD_READ; - cmd[1] = offset; - mutex_lock(&ks->lock); err = spi_sync(ks->spi, &m); mutex_unlock(&ks->lock); @@ -141,20 +224,20 @@ static int ks8995_read(struct ks8995_switch *ks, char *buf, return err ? err : count; } - static int ks8995_write(struct ks8995_switch *ks, char *buf, unsigned offset, size_t count) { - u8 cmd[2]; + __be16 cmd; struct spi_transfer t[2]; struct spi_message m; int err; + cmd = create_spi_cmd(ks, KS8995_CMD_WRITE, offset); spi_message_init(&m); memset(&t, 0, sizeof(t)); - t[0].tx_buf = cmd; + t[0].tx_buf = &cmd; t[0].len = sizeof(cmd); spi_message_add_tail(&t[0], &m); @@ -162,9 +245,6 @@ static int ks8995_write(struct ks8995_switch *ks, char *buf, t[1].len = count; spi_message_add_tail(&t[1], &m); - cmd[0] = KS8995_CMD_WRITE; - cmd[1] = offset; - mutex_lock(&ks->lock); err = spi_sync(ks->spi, &m); mutex_unlock(&ks->lock); @@ -233,6 +313,107 @@ static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj, return ks8995_write(ks8995, buf, off, count); } +/* ks8995_get_revision - get chip revision + * @ks: pointer to switch instance + * + * Verify chip family and id and get chip revision. + */ +static int ks8995_get_revision(struct ks8995_switch *ks) +{ + int err; + u8 id0, id1, ksz8864_id; + + /* read family id */ + err = ks8995_read_reg(ks, KS8995_REG_ID0, &id0); + if (err) { + err = -EIO; + goto err_out; + } + + /* verify family id */ + if (id0 != ks->chip->family_id) { + dev_err(&ks->spi->dev, "chip family id mismatch: expected 0x%02x but 0x%02x read\n", + ks->chip->family_id, id0); + err = -ENODEV; + goto err_out; + } + + switch (ks->chip->family_id) { + case FAMILY_KS8995: + /* try reading chip id at CHIP ID1 */ + err = ks8995_read_reg(ks, KS8995_REG_ID1, &id1); + if (err) { + err = -EIO; + goto err_out; + } + + /* verify chip id */ + if ((get_chip_id(id1) == CHIPID_M) && + (get_chip_id(id1) == ks->chip->chip_id)) { + /* KS8995MA */ + ks->revision_id = get_chip_rev(id1); + } else if (get_chip_id(id1) != CHIPID_M) { + /* KSZ8864RMN */ + err = ks8995_read_reg(ks, KS8995_REG_ID1, &ksz8864_id); + if (err) { + err = -EIO; + goto err_out; + } + + if ((ksz8864_id & 0x80) && + (ks->chip->chip_id == KSZ8864_CHIP_ID)) { + ks->revision_id = get_chip_rev(id1); + } + + } else { + dev_err(&ks->spi->dev, "unsupported chip id for KS8995 family: 0x%02x\n", + id1); + err = -ENODEV; + } + break; + case FAMILY_KSZ8795: + /* try reading chip id at CHIP ID1 */ + err = ks8995_read_reg(ks, KS8995_REG_ID1, &id1); + if (err) { + err = -EIO; + goto err_out; + } + + if (get_chip_id(id1) == ks->chip->chip_id) { + ks->revision_id = get_chip_rev(id1); + } else { + dev_err(&ks->spi->dev, "unsupported chip id for KSZ8795 family: 0x%02x\n", + id1); + err = -ENODEV; + } + break; + default: + dev_err(&ks->spi->dev, "unsupported family id: 0x%02x\n", id0); + err = -ENODEV; + break; + } +err_out: + return err; +} + +/* ks8995_parse_dt - setup platform data from devicetree + * @ks: pointer to switch instance + * + * Parses supported DT properties and sets up platform data + * accordingly. + */ +static void ks8995_parse_dt(struct ks8995_switch *ks) +{ + struct device_node *np = ks->spi->dev.of_node; + struct ks8995_pdata *pdata = ks->pdata; + + if (!np) + return; + + pdata->reset_gpio = of_get_named_gpio_flags(np, "reset-gpios", 0, + &pdata->reset_gpio_flags); +} + static const struct bin_attribute ks8995_registers_attr = { .attr = { .name = "registers", @@ -244,24 +425,58 @@ static const struct bin_attribute ks8995_registers_attr = { }; /* ------------------------------------------------------------------------ */ - static int ks8995_probe(struct spi_device *spi) { - struct ks8995_switch *ks; - struct ks8995_pdata *pdata; - u8 ids[2]; - int err; + struct ks8995_switch *ks; + int err; + int variant = spi_get_device_id(spi)->driver_data; - /* Chip description */ - pdata = spi->dev.platform_data; + if (variant >= max_variant) { + dev_err(&spi->dev, "bad chip variant %d\n", variant); + return -ENODEV; + } ks = devm_kzalloc(&spi->dev, sizeof(*ks), GFP_KERNEL); if (!ks) return -ENOMEM; mutex_init(&ks->lock); - ks->pdata = pdata; ks->spi = spi_dev_get(spi); + ks->chip = &ks8995_chip[variant]; + + if (ks->spi->dev.of_node) { + ks->pdata = devm_kzalloc(&spi->dev, sizeof(*ks->pdata), + GFP_KERNEL); + if (!ks->pdata) + return -ENOMEM; + + ks->pdata->reset_gpio = -1; + + ks8995_parse_dt(ks); + } + + if (!ks->pdata) + ks->pdata = spi->dev.platform_data; + + /* de-assert switch reset */ + if (ks->pdata && gpio_is_valid(ks->pdata->reset_gpio)) { + unsigned long flags; + + flags = (ks->pdata->reset_gpio_flags == OF_GPIO_ACTIVE_LOW ? + GPIOF_ACTIVE_LOW : 0); + + err = devm_gpio_request_one(&spi->dev, + ks->pdata->reset_gpio, + flags, "switch-reset"); + if (err) { + dev_err(&spi->dev, + "failed to get reset-gpios: %d\n", err); + return -EIO; + } + + gpiod_set_value(gpio_to_desc(ks->pdata->reset_gpio), 0); + } + spi_set_drvdata(spi, ks); spi->mode = SPI_MODE_0; @@ -272,39 +487,12 @@ static int ks8995_probe(struct spi_device *spi) return err; } - err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids)); - if (err < 0) { - dev_err(&spi->dev, "unable to read id registers, err=%d\n", - err); + err = ks8995_get_revision(ks); + if (err) return err; - } - - switch (ids[0]) { - case FAMILY_KS8995: - break; - default: - dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]); - return -ENODEV; - } + ks->regs_attr.size = ks->chip->regs_size; memcpy(&ks->regs_attr, &ks8995_registers_attr, sizeof(ks->regs_attr)); - if (get_chip_id(ids[1]) != CHIPID_M) { - u8 val; - - /* Check if this is a KSZ8864RMN */ - err = ks8995_read(ks, &val, KSZ8864_REG_ID1, sizeof(val)); - if (err < 0) { - dev_err(&spi->dev, - "unable to read chip id register, err=%d\n", - err); - return err; - } - if ((val & 0x80) == 0) { - dev_err(&spi->dev, "unknown chip:%02x,0\n", ids[1]); - return err; - } - ks->regs_attr.size = KSZ8864_REGS_SIZE; - } err = ks8995_reset(ks); if (err) @@ -317,14 +505,8 @@ static int ks8995_probe(struct spi_device *spi) return err; } - if (get_chip_id(ids[1]) == CHIPID_M) { - dev_info(&spi->dev, - "KS8995 device found, Chip ID:%x, Revision:%x\n", - get_chip_id(ids[1]), get_chip_rev(ids[1])); - } else { - dev_info(&spi->dev, "KSZ8864 device found, Revision:%x\n", - get_chip_rev(ids[1])); - } + dev_info(&spi->dev, "%s device found, Chip ID:%x, Revision:%x\n", + ks->chip->name, ks->chip->chip_id, ks->revision_id); return 0; } @@ -335,17 +517,21 @@ static int ks8995_remove(struct spi_device *spi) sysfs_remove_bin_file(&spi->dev.kobj, &ks->regs_attr); + /* assert reset */ + if (ks->pdata && gpio_is_valid(ks->pdata->reset_gpio)) + gpiod_set_value(gpio_to_desc(ks->pdata->reset_gpio), 1); + return 0; } /* ------------------------------------------------------------------------ */ - static struct spi_driver ks8995_driver = { .driver = { .name = "spi-ks8995", }, .probe = ks8995_probe, .remove = ks8995_remove, + .id_table = ks8995_id, }; module_spi_driver(ks8995_driver); |