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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/net/phy/spi_ks8995.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/phy/spi_ks8995.c')
-rw-r--r--drivers/net/phy/spi_ks8995.c506
1 files changed, 506 insertions, 0 deletions
diff --git a/drivers/net/phy/spi_ks8995.c b/drivers/net/phy/spi_ks8995.c
new file mode 100644
index 0000000000..7196e927c2
--- /dev/null
+++ b/drivers/net/phy/spi_ks8995.c
@@ -0,0 +1,506 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPI driver for Micrel/Kendin KS8995M and KSZ8864RMN ethernet switches
+ *
+ * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
+ *
+ * This file was based on: drivers/spi/at25.c
+ * Copyright (C) 2006 David Brownell
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+
+#include <linux/spi/spi.h>
+
+#define DRV_VERSION "0.1.1"
+#define DRV_DESC "Micrel KS8995 Ethernet switch SPI driver"
+
+/* ------------------------------------------------------------------------ */
+
+#define KS8995_REG_ID0 0x00 /* Chip ID0 */
+#define KS8995_REG_ID1 0x01 /* Chip ID1 */
+
+#define KS8995_REG_GC0 0x02 /* Global Control 0 */
+#define KS8995_REG_GC1 0x03 /* Global Control 1 */
+#define KS8995_REG_GC2 0x04 /* Global Control 2 */
+#define KS8995_REG_GC3 0x05 /* Global Control 3 */
+#define KS8995_REG_GC4 0x06 /* Global Control 4 */
+#define KS8995_REG_GC5 0x07 /* Global Control 5 */
+#define KS8995_REG_GC6 0x08 /* Global Control 6 */
+#define KS8995_REG_GC7 0x09 /* Global Control 7 */
+#define KS8995_REG_GC8 0x0a /* Global Control 8 */
+#define KS8995_REG_GC9 0x0b /* Global Control 9 */
+
+#define KS8995_REG_PC(p, r) ((0x10 * p) + r) /* Port Control */
+#define KS8995_REG_PS(p, r) ((0x10 * p) + r + 0xe) /* Port Status */
+
+#define KS8995_REG_TPC0 0x60 /* TOS Priority Control 0 */
+#define KS8995_REG_TPC1 0x61 /* TOS Priority Control 1 */
+#define KS8995_REG_TPC2 0x62 /* TOS Priority Control 2 */
+#define KS8995_REG_TPC3 0x63 /* TOS Priority Control 3 */
+#define KS8995_REG_TPC4 0x64 /* TOS Priority Control 4 */
+#define KS8995_REG_TPC5 0x65 /* TOS Priority Control 5 */
+#define KS8995_REG_TPC6 0x66 /* TOS Priority Control 6 */
+#define KS8995_REG_TPC7 0x67 /* TOS Priority Control 7 */
+
+#define KS8995_REG_MAC0 0x68 /* MAC address 0 */
+#define KS8995_REG_MAC1 0x69 /* MAC address 1 */
+#define KS8995_REG_MAC2 0x6a /* MAC address 2 */
+#define KS8995_REG_MAC3 0x6b /* MAC address 3 */
+#define KS8995_REG_MAC4 0x6c /* MAC address 4 */
+#define KS8995_REG_MAC5 0x6d /* MAC address 5 */
+
+#define KS8995_REG_IAC0 0x6e /* Indirect Access Control 0 */
+#define KS8995_REG_IAC1 0x6f /* Indirect Access Control 0 */
+#define KS8995_REG_IAD7 0x70 /* Indirect Access Data 7 */
+#define KS8995_REG_IAD6 0x71 /* Indirect Access Data 6 */
+#define KS8995_REG_IAD5 0x72 /* Indirect Access Data 5 */
+#define KS8995_REG_IAD4 0x73 /* Indirect Access Data 4 */
+#define KS8995_REG_IAD3 0x74 /* Indirect Access Data 3 */
+#define KS8995_REG_IAD2 0x75 /* Indirect Access Data 2 */
+#define KS8995_REG_IAD1 0x76 /* Indirect Access Data 1 */
+#define KS8995_REG_IAD0 0x77 /* Indirect Access Data 0 */
+
+#define KSZ8864_REG_ID1 0xfe /* Chip ID in bit 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
+#define ID1_REVISION_M 0x7
+#define ID1_REVISION_S 1
+#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_switch {
+ struct spi_device *spi;
+ struct mutex lock;
+ struct gpio_desc *reset_gpio;
+ 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 const struct of_device_id ks8895_spi_of_match[] = {
+ { .compatible = "micrel,ks8995" },
+ { .compatible = "micrel,ksz8864" },
+ { .compatible = "micrel,ksz8795" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ks8895_spi_of_match);
+
+static inline u8 get_chip_id(u8 val)
+{
+ return (val >> ID1_CHIPID_S) & ID1_CHIPID_M;
+}
+
+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)
+{
+ __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].len = sizeof(cmd);
+ spi_message_add_tail(&t[0], &m);
+
+ t[1].rx_buf = buf;
+ t[1].len = count;
+ spi_message_add_tail(&t[1], &m);
+
+ mutex_lock(&ks->lock);
+ err = spi_sync(ks->spi, &m);
+ mutex_unlock(&ks->lock);
+
+ return err ? err : count;
+}
+
+static int ks8995_write(struct ks8995_switch *ks, char *buf,
+ unsigned offset, size_t count)
+{
+ __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].len = sizeof(cmd);
+ spi_message_add_tail(&t[0], &m);
+
+ t[1].tx_buf = buf;
+ t[1].len = count;
+ spi_message_add_tail(&t[1], &m);
+
+ mutex_lock(&ks->lock);
+ err = spi_sync(ks->spi, &m);
+ mutex_unlock(&ks->lock);
+
+ return err ? err : count;
+}
+
+static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
+{
+ return ks8995_read(ks, buf, addr, 1) != 1;
+}
+
+static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
+{
+ char buf = val;
+
+ return ks8995_write(ks, &buf, addr, 1) != 1;
+}
+
+/* ------------------------------------------------------------------------ */
+
+static int ks8995_stop(struct ks8995_switch *ks)
+{
+ return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
+}
+
+static int ks8995_start(struct ks8995_switch *ks)
+{
+ return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
+}
+
+static int ks8995_reset(struct ks8995_switch *ks)
+{
+ int err;
+
+ err = ks8995_stop(ks);
+ if (err)
+ return err;
+
+ udelay(KS8995_RESET_DELAY);
+
+ return ks8995_start(ks);
+}
+
+static ssize_t ks8995_registers_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
+{
+ struct device *dev;
+ struct ks8995_switch *ks8995;
+
+ dev = kobj_to_dev(kobj);
+ ks8995 = dev_get_drvdata(dev);
+
+ return ks8995_read(ks8995, buf, off, count);
+}
+
+static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
+{
+ struct device *dev;
+ struct ks8995_switch *ks8995;
+
+ dev = kobj_to_dev(kobj);
+ ks8995 = dev_get_drvdata(dev);
+
+ 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;
+}
+
+static const struct bin_attribute ks8995_registers_attr = {
+ .attr = {
+ .name = "registers",
+ .mode = 0600,
+ },
+ .size = KS8995_REGS_SIZE,
+ .read = ks8995_registers_read,
+ .write = ks8995_registers_write,
+};
+
+/* ------------------------------------------------------------------------ */
+static int ks8995_probe(struct spi_device *spi)
+{
+ struct ks8995_switch *ks;
+ int err;
+ int variant = spi_get_device_id(spi)->driver_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->spi = spi;
+ ks->chip = &ks8995_chip[variant];
+
+ ks->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
+ GPIOD_OUT_HIGH);
+ err = PTR_ERR_OR_ZERO(ks->reset_gpio);
+ if (err) {
+ dev_err(&spi->dev,
+ "failed to get reset gpio: %d\n", err);
+ return err;
+ }
+
+ err = gpiod_set_consumer_name(ks->reset_gpio, "switch-reset");
+ if (err)
+ return err;
+
+ /* de-assert switch reset */
+ /* FIXME: this likely requires a delay */
+ gpiod_set_value_cansleep(ks->reset_gpio, 0);
+
+ spi_set_drvdata(spi, ks);
+
+ spi->mode = SPI_MODE_0;
+ spi->bits_per_word = 8;
+ err = spi_setup(spi);
+ if (err) {
+ dev_err(&spi->dev, "spi_setup failed, err=%d\n", err);
+ return err;
+ }
+
+ err = ks8995_get_revision(ks);
+ if (err)
+ return err;
+
+ memcpy(&ks->regs_attr, &ks8995_registers_attr, sizeof(ks->regs_attr));
+ ks->regs_attr.size = ks->chip->regs_size;
+
+ err = ks8995_reset(ks);
+ if (err)
+ return err;
+
+ sysfs_attr_init(&ks->regs_attr.attr);
+ err = sysfs_create_bin_file(&spi->dev.kobj, &ks->regs_attr);
+ if (err) {
+ dev_err(&spi->dev, "unable to create sysfs file, err=%d\n",
+ err);
+ return err;
+ }
+
+ 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;
+}
+
+static void ks8995_remove(struct spi_device *spi)
+{
+ struct ks8995_switch *ks = spi_get_drvdata(spi);
+
+ sysfs_remove_bin_file(&spi->dev.kobj, &ks->regs_attr);
+
+ /* assert reset */
+ gpiod_set_value_cansleep(ks->reset_gpio, 1);
+}
+
+/* ------------------------------------------------------------------------ */
+static struct spi_driver ks8995_driver = {
+ .driver = {
+ .name = "spi-ks8995",
+ .of_match_table = ks8895_spi_of_match,
+ },
+ .probe = ks8995_probe,
+ .remove = ks8995_remove,
+ .id_table = ks8995_id,
+};
+
+module_spi_driver(ks8995_driver);
+
+MODULE_DESCRIPTION(DRV_DESC);
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
+MODULE_LICENSE("GPL v2");