ramips: update i2c drivers

* add rt_i2c structure to store driver data
* rewrite read/write check function and add i2c error status check.
  so we don't need to wait until time out.
* add 10 bits address support. according to the data sheet i think
  it is possible. but i haven't verify it.
* the most important is start transfer only need once. otherwise
  it cause I2C_STARTERR status.
* add set i2c clock speed register by dts options "clock-frequency".
  not just hard code it.
* add mt7621 i2c driver. i just copy i2c-ralink.c and change register
  names. and the hardware don't support error status. so i remove it.
  but the logic is the same.

Signed-off-by: Michael Lee <igvtee@gmail.com>
v19.07.3_mercusys_ac12_duma
Michael Lee 9 years ago committed by John Crispin
parent 66ffd0ddf9
commit 60ccfbbad0

@ -45,12 +45,13 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+};
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -806,6 +806,10 @@ config I2C_RK3X
@@ -806,6 +806,11 @@ config I2C_RK3X
This driver can also be built as a module. If so, the module will
be called i2c-rk3x.
+config I2C_RALINK
+ tristate "Ralink I2C Controller"
+ depends on RALINK && !SOC_MT7621
+ select OF_I2C
+
config HAVE_S3C2410_I2C
@ -68,11 +69,12 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o
--- /dev/null
+++ b/drivers/i2c/busses/i2c-ralink.c
@@ -0,0 +1,327 @@
@@ -0,0 +1,435 @@
+/*
+ * drivers/i2c/busses/i2c-ralink.c
+ *
+ * Copyright (C) 2013 Steven Liu <steven_liu@mediatek.com>
+ * Copyright (C) 2016 Michael Lee <igvtee@gmail.com>
+ *
+ * Improve driver for i2cdetect from i2c-tools to detect i2c devices on the bus.
+ * (C) 2014 Sittisak <sittisaks@hotmail.com>
@ -101,8 +103,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+#include <asm/mach-ralink/ralink_regs.h>
+#include <linux/clk.h>
+
+#define REG_CONFIG_REG 0x00
+#define REG_CLKDIV_REG 0x04
@ -113,191 +114,250 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+#define REG_STATUS_REG 0x18
+#define REG_STARTXFR_REG 0x1C
+#define REG_BYTECNT_REG 0x20
+#define REG_SM0CFG2 0x28
+#define REG_SM0CTL0 0x40
+
+/* REG_CONFIG_REG */
+#define I2C_ADDRLEN_OFFSET 5
+#define I2C_DEVADLEN_OFFSET 2
+#define I2C_ADDRLEN_MASK 0x3
+#define I2C_ADDR_DIS BIT(1)
+#define I2C_DEVADDR_DIS BIT(0)
+#define I2C_ADDRLEN_8 (7 << I2C_ADDRLEN_OFFSET)
+#define I2C_DEVADLEN_7 (6 << I2C_DEVADLEN_OFFSET)
+#define I2C_CONF_DEFAULT (I2C_ADDRLEN_8 | I2C_DEVADLEN_7)
+
+/* REG_CLKDIV_REG */
+#define I2C_CLKDIV_MASK 0xffff
+
+/* REG_DEVADDR_REG */
+#define I2C_DEVADDR_MASK 0x7f
+
+/* REG_ADDR_REG */
+#define I2C_ADDR_MASK 0xff
+
+/* REG_STATUS_REG */
+#define I2C_STARTERR BIT(4)
+#define I2C_ACKERR BIT(3)
+#define I2C_DATARDY BIT(2)
+#define I2C_SDOEMPTY BIT(1)
+#define I2C_BUSY BIT(0)
+
+#define I2C_DEVADLEN_7 (6 << 2)
+#define I2C_ADDRDIS BIT(1)
+/* REG_STARTXFR_REG */
+#define NOSTOP_CMD BIT(2)
+#define NODATA_CMD BIT(1)
+#define READ_CMD BIT(0)
+
+#define CLKDIV_VALUE 200 // clock rate is 40M, 40M / (200*2) = 100k (standard i2c bus rate).
+//#define CLKDIV_VALUE 50 // clock rate is 40M, 40M / (50*2) = 400k (fast i2c bus rate).
+
+#define READ_CMD 0x01
+#define WRITE_CMD 0x00
+#define READ_BLOCK 64
+
+#define SM0CTL0_OD BIT(31)
+#define SM0CTL0_VTRIG BIT(28)
+#define SM0CTL0_OUTHI BIT(6)
+#define SM0CTL0_STRETCH BIT(1)
+#define SM0CTL0_DEFAULT (SM0CTL0_OD | SM0CTL0_VTRIG | SM0CTL0_OUTHI | SM0CTL0_STRETCH)
+/* REG_BYTECNT_REG */
+#define BYTECNT_MAX 64
+#define SET_BYTECNT(x) (x - 1)
+
+/* timeout waiting for I2C devices to respond (clock streching) */
+#define RT_I2C_TIMEOUT (msecs_to_jiffies(1000))
+
+enum {
+ I2C_TYPE_RALINK,
+ I2C_TYPE_MEDIATEK,
+#define TIMEOUT_MS 1000
+#define DELAY_INTERVAL_US 100
+
+struct rt_i2c {
+ void __iomem *base;
+ struct clk *clk;
+ struct device *dev;
+ struct i2c_adapter adap;
+ u32 cur_clk;
+ u32 clk_div;
+ u32 flags;
+};
+
+static void __iomem *membase;
+static struct i2c_adapter *adapter;
+static int hw_type;
+
+static void rt_i2c_w32(u32 val, unsigned reg)
+static void rt_i2c_w32(struct rt_i2c *i2c, u32 val, unsigned reg)
+{
+ iowrite32(val, membase + reg);
+ iowrite32(val, i2c->base + reg);
+}
+
+static u32 rt_i2c_r32(unsigned reg)
+static u32 rt_i2c_r32(struct rt_i2c *i2c, unsigned reg)
+{
+ return ioread32(membase + reg);
+ return ioread32(i2c->base + reg);
+}
+
+static inline int rt_i2c_get_ack(void)
+static int poll_down_timeout(void __iomem *addr, u32 mask)
+{
+ return (rt_i2c_r32(REG_STATUS_REG) & I2C_ACKERR) ? -EIO : 0;
+}
+
+static inline int rt_i2c_wait_rx_done(void)
+{
+ unsigned long timeout;
+
+ timeout = jiffies + RT_I2C_TIMEOUT;
+ unsigned long timeout = jiffies + msecs_to_jiffies(TIMEOUT_MS);
+
+ do {
+ if (time_after(jiffies, timeout))
+ return (-ETIMEDOUT);
+ if (!(readl_relaxed(addr) & mask))
+ return 0;
+
+ } while (!(rt_i2c_r32(REG_STATUS_REG) & I2C_DATARDY));
+ usleep_range(DELAY_INTERVAL_US, DELAY_INTERVAL_US + 50);
+ } while (time_before(jiffies, timeout));
+
+ return 0;
+ return (readl_relaxed(addr) & mask) ? -EAGAIN : 0;
+}
+
+static inline int rt_i2c_wait_idle(void)
+static int rt_i2c_wait_idle(struct rt_i2c *i2c)
+{
+ unsigned long timeout;
+ int ret;
+
+ timeout = jiffies + RT_I2C_TIMEOUT;
+ ret = poll_down_timeout(i2c->base + REG_STATUS_REG, I2C_BUSY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "idle err(%d)\n", ret);
+
+ do {
+ if (time_after(jiffies, timeout)) {
+ printk("i2c-read line busy\n");
+ return 1;
+ }
+ } while (rt_i2c_r32(REG_STATUS_REG) & I2C_BUSY);
+
+ return 0;
+ return ret;
+}
+
+static inline int rt_i2c_wait_tx_done(void)
+static int poll_up_timeout(void __iomem *addr, u32 mask)
+{
+ unsigned long timeout;
+
+ timeout = jiffies + RT_I2C_TIMEOUT;
+ unsigned long timeout = jiffies + msecs_to_jiffies(TIMEOUT_MS);
+ u32 status;
+
+ do {
+ if (time_after(jiffies, timeout))
+ return (-ETIMEDOUT);
+ status = readl_relaxed(addr);
+
+ } while (!(rt_i2c_r32(REG_STATUS_REG) & I2C_SDOEMPTY));
+ /* check error status */
+ if (status & I2C_STARTERR)
+ return -EAGAIN;
+ else if (status & I2C_ACKERR)
+ return -ENXIO;
+ else if (status & mask)
+ return 0;
+
+ return 0;
+ usleep_range(DELAY_INTERVAL_US, DELAY_INTERVAL_US + 50);
+ } while (time_before(jiffies, timeout));
+
+ return -ETIMEDOUT;
+}
+
+static int rt_i2c_handle_msg(struct i2c_adapter *a, struct i2c_msg* msg)
+static int rt_i2c_wait_rx_done(struct rt_i2c *i2c)
+{
+ int i = 0, j = 0, pos = 0;
+ int nblock = msg->len / READ_BLOCK;
+ int rem = msg->len % READ_BLOCK;
+ int ret = 0;
+
+ if (msg->flags & I2C_M_TEN) {
+ printk("10 bits addr not supported\n");
+ return -EINVAL;
+ }
+
+ if (msg->flags & I2C_M_RD) {
+ for (i = 0; i < nblock; i++) {
+ if (rt_i2c_wait_idle())
+ return -ETIMEDOUT;
+ rt_i2c_w32(READ_BLOCK - 1, REG_BYTECNT_REG);
+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
+ for (j = 0; j < READ_BLOCK; j++) {
+ if (rt_i2c_wait_rx_done() < 0)
+ ret = rt_i2c_wait_rx_done();
+ if (rt_i2c_get_ack() < 0)
+ ret = rt_i2c_get_ack();
+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
+ }
+ }
+
+ if (rt_i2c_wait_idle())
+ return -ETIMEDOUT;
+ if (rem) {
+ rt_i2c_w32(rem - 1, REG_BYTECNT_REG);
+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
+ }
+ for (i = 0; i < rem; i++) {
+ if (rt_i2c_wait_rx_done() < 0)
+ ret = rt_i2c_wait_rx_done();
+ if (rt_i2c_get_ack() < 0)
+ ret = rt_i2c_get_ack();
+ int ret;
+
+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
+ }
+ } else {
+ if (rt_i2c_wait_idle())
+ return -ETIMEDOUT;
+ rt_i2c_w32(msg->len - 1, REG_BYTECNT_REG);
+ for (i = 0; i < msg->len; i++) {
+ rt_i2c_w32(msg->buf[i], REG_DATAOUT_REG);
+ rt_i2c_w32(WRITE_CMD, REG_STARTXFR_REG);
+
+ if (rt_i2c_wait_tx_done() < 0)
+ ret = rt_i2c_wait_tx_done();
+ if (rt_i2c_get_ack() < 0)
+ ret = rt_i2c_get_ack();
+ }
+ }
+ ret = poll_up_timeout(i2c->base + REG_STATUS_REG, I2C_DATARDY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "rx err(%d)\n", ret);
+
+ return ret;
+}
+
+static int rt_i2c_master_xfer(struct i2c_adapter *a, struct i2c_msg *m, int n)
+static int rt_i2c_wait_tx_done(struct rt_i2c *i2c)
+{
+ int i = 0;
+ int ret = 0;
+ int ret;
+
+ if (rt_i2c_wait_idle())
+ return -ETIMEDOUT;
+ ret = poll_up_timeout(i2c->base + REG_STATUS_REG, I2C_SDOEMPTY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "tx err(%d)\n", ret);
+
+ device_reset(a->dev.parent);
+ return ret;
+}
+
+ rt_i2c_w32(m->addr, REG_DEVADDR_REG);
+ rt_i2c_w32(I2C_DEVADLEN_7 | I2C_ADDRDIS, REG_CONFIG_REG);
+ if (hw_type == I2C_TYPE_RALINK) {
+ rt_i2c_w32(CLKDIV_VALUE, REG_CLKDIV_REG);
+ } else {
+ rt_i2c_w32((CLKDIV_VALUE << 16) | SM0CTL0_DEFAULT, REG_SM0CTL0);
+ rt_i2c_w32(1, REG_SM0CFG2);
+ }
+static void rt_i2c_reset(struct rt_i2c *i2c)
+{
+ device_reset(i2c->adap.dev.parent);
+ barrier();
+ rt_i2c_w32(i2c, i2c->clk_div, REG_CLKDIV_REG);
+}
+
+static void rt_i2c_dump_reg(struct rt_i2c *i2c)
+{
+ dev_dbg(i2c->dev, "conf %08x, clkdiv %08x, devaddr %08x, " \
+ "addr %08x, dataout %08x, datain %08x, " \
+ "status %08x, startxfr %08x, bytecnt %08x\n",
+ rt_i2c_r32(i2c, REG_CONFIG_REG),
+ rt_i2c_r32(i2c, REG_CLKDIV_REG),
+ rt_i2c_r32(i2c, REG_DEVADDR_REG),
+ rt_i2c_r32(i2c, REG_ADDR_REG),
+ rt_i2c_r32(i2c, REG_DATAOUT_REG),
+ rt_i2c_r32(i2c, REG_DATAIN_REG),
+ rt_i2c_r32(i2c, REG_STATUS_REG),
+ rt_i2c_r32(i2c, REG_STARTXFR_REG),
+ rt_i2c_r32(i2c, REG_BYTECNT_REG));
+}
+
+ for (i = 0; i < n && !ret; i++) {
+ ret = rt_i2c_handle_msg(a, &m[i]);
+static int rt_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ struct rt_i2c *i2c;
+ struct i2c_msg *pmsg;
+ unsigned char addr;
+ int i, j, ret;
+ u32 cmd;
+
+ i2c = i2c_get_adapdata(adap);
+
+ for (i = 0; i < num; i++) {
+ pmsg = &msgs[i];
+ if (i == (num - 1))
+ cmd = 0;
+ else
+ cmd = NOSTOP_CMD;
+
+ dev_dbg(i2c->dev, "addr: 0x%x, len: %d, flags: 0x%x, stop: %d\n",
+ pmsg->addr, pmsg->len, pmsg->flags,
+ (cmd == 0)? 1 : 0);
+
+ /* wait hardware idle */
+ if ((ret = rt_i2c_wait_idle(i2c)))
+ goto err_timeout;
+
+ if (pmsg->flags & I2C_M_TEN) {
+ rt_i2c_w32(i2c, I2C_CONF_DEFAULT, REG_CONFIG_REG);
+ /* 10 bits address */
+ addr = 0x78 | ((pmsg->addr >> 8) & 0x03);
+ rt_i2c_w32(i2c, addr & I2C_DEVADDR_MASK,
+ REG_DEVADDR_REG);
+ rt_i2c_w32(i2c, pmsg->addr & I2C_ADDR_MASK,
+ REG_ADDR_REG);
+ } else {
+ rt_i2c_w32(i2c, I2C_CONF_DEFAULT | I2C_ADDR_DIS,
+ REG_CONFIG_REG);
+ /* 7 bits address */
+ rt_i2c_w32(i2c, pmsg->addr & I2C_DEVADDR_MASK,
+ REG_DEVADDR_REG);
+ }
+
+ if (ret < 0) {
+ return ret;
+ /* buffer length */
+ if (pmsg->len == 0)
+ cmd |= NODATA_CMD;
+ else
+ rt_i2c_w32(i2c, SET_BYTECNT(pmsg->len),
+ REG_BYTECNT_REG);
+
+ j = 0;
+ if (pmsg->flags & I2C_M_RD) {
+ cmd |= READ_CMD;
+ /* start transfer */
+ barrier();
+ rt_i2c_w32(i2c, cmd, REG_STARTXFR_REG);
+ do {
+ /* wait */
+ if ((ret = rt_i2c_wait_rx_done(i2c)))
+ goto err_timeout;
+ /* read data */
+ if (pmsg->len)
+ pmsg->buf[j] = rt_i2c_r32(i2c,
+ REG_DATAIN_REG);
+ j++;
+ } while (j < pmsg->len);
+ } else {
+ do {
+ /* write data */
+ if (pmsg->len)
+ rt_i2c_w32(i2c, pmsg->buf[j],
+ REG_DATAOUT_REG);
+ /* start transfer */
+ if (j == 0) {
+ barrier();
+ rt_i2c_w32(i2c, cmd, REG_STARTXFR_REG);
+ }
+ /* wait */
+ if ((ret = rt_i2c_wait_tx_done(i2c)))
+ goto err_timeout;
+ j++;
+ } while (j < pmsg->len);
+ }
+ }
+ /* the return value is number of executed messages */
+ ret = i;
+
+ return ret;
+
+ return n;
+err_timeout:
+ rt_i2c_dump_reg(i2c);
+ rt_i2c_reset(i2c);
+ return ret;
+}
+
+static u32 rt_i2c_func(struct i2c_adapter *a)
@ -311,60 +371,110 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+};
+
+static const struct of_device_id i2c_rt_dt_ids[] = {
+ { .compatible = "ralink,rt2880-i2c", .data = (void *) I2C_TYPE_RALINK },
+ { .compatible = "mediatek,mt7628-i2c", .data = (void *) I2C_TYPE_MEDIATEK },
+ { .compatible = "ralink,rt2880-i2c" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, i2c_rt_dt_ids);
+
+static struct i2c_adapter_quirks rt_i2c_quirks = {
+ .max_write_len = BYTECNT_MAX,
+ .max_read_len = BYTECNT_MAX,
+};
+
+static int rt_i2c_init(struct rt_i2c *i2c)
+{
+ u32 reg;
+
+ /* i2c_sclk = periph_clk / ((2 * clk_div) + 5) */
+ i2c->clk_div = (clk_get_rate(i2c->clk) - (5 * i2c->cur_clk)) /
+ (2 * i2c->cur_clk);
+ if (i2c->clk_div < 8)
+ i2c->clk_div = 8;
+ if (i2c->clk_div > I2C_CLKDIV_MASK)
+ i2c->clk_div = I2C_CLKDIV_MASK;
+
+ /* check support combinde/repeated start message */
+ rt_i2c_w32(i2c, NOSTOP_CMD, REG_STARTXFR_REG);
+ reg = rt_i2c_r32(i2c, REG_STARTXFR_REG) & NOSTOP_CMD;
+
+ rt_i2c_reset(i2c);
+
+ return reg;
+}
+
+static int rt_i2c_probe(struct platform_device *pdev)
+{
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ struct resource *res;
+ struct rt_i2c *i2c;
+ struct i2c_adapter *adap;
+ const struct of_device_id *match;
+ int ret;
+ int ret, restart;
+
+ match = of_match_device(i2c_rt_dt_ids, &pdev->dev);
+ hw_type = (int) match->data;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no memory resource found\n");
+ return -ENODEV;
+ }
+
+ adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter), GFP_KERNEL);
+ if (!adapter) {
+ i2c = devm_kzalloc(&pdev->dev, sizeof(struct rt_i2c), GFP_KERNEL);
+ if (!i2c) {
+ dev_err(&pdev->dev, "failed to allocate i2c_adapter\n");
+ return -ENOMEM;
+ }
+
+ membase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(membase))
+ return PTR_ERR(membase);
+
+ strlcpy(adapter->name, dev_name(&pdev->dev), sizeof(adapter->name));
+ adapter->owner = THIS_MODULE;
+ adapter->nr = pdev->id;
+ adapter->timeout = HZ;
+ adapter->algo = &rt_i2c_algo;
+ adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adapter->dev.parent = &pdev->dev;
+ adapter->dev.of_node = pdev->dev.of_node;
+
+ ret = i2c_add_numbered_adapter(adapter);
+ if (ret)
+ return ret;
+ i2c->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(i2c->base))
+ return PTR_ERR(i2c->base);
+
+ platform_set_drvdata(pdev, adapter);
+ i2c->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c->clk)) {
+ dev_err(&pdev->dev, "no clock defined\n");
+ return -ENODEV;
+ }
+ clk_prepare_enable(i2c->clk);
+ i2c->dev = &pdev->dev;
+
+ if (of_property_read_u32(pdev->dev.of_node,
+ "clock-frequency", &i2c->cur_clk))
+ i2c->cur_clk = 100000;
+
+ adap = &i2c->adap;
+ adap->owner = THIS_MODULE;
+ adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adap->algo = &rt_i2c_algo;
+ adap->retries = 3;
+ adap->dev.parent = &pdev->dev;
+ i2c_set_adapdata(adap, i2c);
+ adap->dev.of_node = pdev->dev.of_node;
+ strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
+ adap->quirks = &rt_i2c_quirks;
+
+ platform_set_drvdata(pdev, i2c);
+
+ restart = rt_i2c_init(i2c);
+
+ ret = i2c_add_adapter(adap);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add adapter\n");
+ clk_disable_unprepare(i2c->clk);
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "loaded\n");
+ dev_info(&pdev->dev, "clock %uKHz, re-start %ssupport\n",
+ i2c->cur_clk/1000, restart ? "" : "not ");
+
+ return 0;
+ return ret;
+}
+
+static int rt_i2c_remove(struct platform_device *pdev)
+{
+ platform_set_drvdata(pdev, NULL);
+ struct rt_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+ clk_disable_unprepare(i2c->clk);
+
+ return 0;
+}
@ -389,8 +499,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+{
+ platform_driver_unregister(&rt_i2c_driver);
+}
+
+module_exit (i2c_rt_exit);
+module_exit(i2c_rt_exit);
+
+MODULE_AUTHOR("Steven Liu <steven_liu@mediatek.com>");
+MODULE_DESCRIPTION("Ralink I2c host driver");

@ -13,12 +13,13 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -810,6 +810,10 @@ config I2C_RALINK
tristate "Ralink I2C Controller"
@@ -811,6 +811,11 @@ config I2C_RALINK
depends on RALINK && !SOC_MT7621
select OF_I2C
+config I2C_MT7621
+ tristate "MT7621 I2C Controller"
+ tristate "MT7621/MT7628 I2C Controller"
+ depends on RALINK && (SOC_MT7620 || SOC_MT7621)
+ select OF_I2C
+
config HAVE_S3C2410_I2C
@ -36,11 +37,12 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o
--- /dev/null
+++ b/drivers/i2c/busses/i2c-mt7621.c
@@ -0,0 +1,303 @@
@@ -0,0 +1,433 @@
+/*
+ * drivers/i2c/busses/i2c-mt7621.c
+ *
+ * Copyright (C) 2013 Steven Liu <steven_liu@mediatek.com>
+ * Copyright (C) 2016 Michael Lee <igvtee@gmail.com>
+ *
+ * Improve driver for i2cdetect from i2c-tools to detect i2c devices on the bus.
+ * (C) 2014 Sittisak <sittisaks@hotmail.com>
@ -65,276 +67,405 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+
+#define REG_SM0CFG0 0x08
+#define REG_SM0DOUT 0x10
+#define REG_SM0DIN 0x14
+#define REG_SM0ST 0x18
+#define REG_SM0AUTO 0x1C
+#define REG_SM0CFG1 0x20
+#define REG_SM0CFG2 0x28
+#define REG_SM0CTL0 0x40
+#define REG_SM0CTL1 0x44
+#define REG_SM0D0 0x50
+#define REG_SM0D1 0x54
+#define REG_PINTEN 0x5C
+#define REG_PINTST 0x60
+#define REG_PINTCL 0x64
+
+/* REG_SM0CFG0 */
+#define I2C_DEVADDR_MASK 0x7f
+
+/* REG_SM0ST */
+#define I2C_DATARDY BIT(2)
+#define I2C_SDOEMPTY BIT(1)
+#define I2C_BUSY BIT(0)
+
+/* REG_SM0AUTO */
+#define READ_CMD BIT(0)
+
+/* REG_SM0CFG1 */
+#define BYTECNT_MAX 64
+#define SET_BYTECNT(x) (x - 1)
+
+/* REG_SM0CFG2 */
+#define AUTOMODE_EN BIT(0)
+
+/* REG_SM0CTL0 */
+#define ODRAIN_HIGH_SM0 BIT(31)
+#define VSYNC_SHIFT 28
+#define VSYNC_MASK 0x3
+#define VSYNC_PULSE (0x1 << VSYNC_SHIFT)
+#define VSYNC_RISING (0x2 << VSYNC_SHIFT)
+#define CLK_DIV_SHIFT 16
+#define CLK_DIV_MASK 0xfff
+#define DEG_CNT_SHIFT 8
+#define DEG_CNT_MASK 0xff
+#define WAIT_HIGH BIT(6)
+#define DEG_EN BIT(5)
+#define CS_STATUA BIT(4)
+#define SCL_STATUS BIT(3)
+#define SDA_STATUS BIT(2)
+#define SM0_EN BIT(1)
+#define SCL_STRECH BIT(0)
+
+/* REG_SM0CTL1 */
+#define ACK_SHIFT 16
+#define ACK_MASK 0xff
+#define PGLEN_SHIFT 8
+#define PGLEN_MASK 0x7
+#define SM0_MODE_SHIFT 4
+#define SM0_MODE_MASK 0x7
+#define SM0_MODE_START 0x1
+#define SM0_MODE_WRITE 0x2
+#define SM0_MODE_STOP 0x3
+#define SM0_MODE_READ_NACK 0x4
+#define SM0_MODE_READ_ACK 0x5
+#define SM0_TRI_BUSY BIT(0)
+
+/* timeout waiting for I2C devices to respond (clock streching) */
+#define TIMEOUT_MS 1000
+#define DELAY_INTERVAL_US 100
+
+struct mtk_i2c {
+ void __iomem *base;
+ struct clk *clk;
+ struct device *dev;
+ struct i2c_adapter adap;
+ u32 cur_clk;
+ u32 clk_div;
+ u32 flags;
+};
+
+#include <asm/mach-ralink/ralink_regs.h>
+
+#define REG_CONFIG_REG 0x00
+#define REG_CLKDIV_REG 0x04
+#define REG_DEVADDR_REG 0x08
+#define REG_ADDR_REG 0x0C
+#define REG_DATAOUT_REG 0x10
+#define REG_DATAIN_REG 0x14
+#define REG_STATUS_REG 0x18
+#define REG_STARTXFR_REG 0x1C
+#define REG_BYTECNT_REG 0x20
+#define REG_SM0_IS_AUTOMODE 0x28
+#define REG_SM0CTL0 0x40
+
+
+#define I2C_STARTERR 0x10
+#define I2C_ACKERR 0x08
+#define I2C_DATARDY 0x04
+#define I2C_SDOEMPTY 0x02
+#define I2C_BUSY 0x01
+
+/* I2C_CFG register bit field */
+#define I2C_CFG_ADDRLEN_8 (7<<5) /* 8 bits */
+#define I2C_CFG_DEVADLEN_7 (6<<2)
+#define I2C_CFG_ADDRDIS BIT(1)
+#define I2C_CFG_DEVADDIS BIT(0)
+
+#define I2C_CFG_DEFAULT (I2C_CFG_ADDRLEN_8 | \
+ I2C_CFG_DEVADLEN_7 | \
+ I2C_CFG_ADDRDIS)
+
+#define I2C_RETRY 0x1000
+
+#define CLKDIV_VALUE 333
+#define i2c_busy_loop (CLKDIV_VALUE*30)
+
+#define READ_CMD 0x01
+#define WRITE_CMD 0x00
+#define READ_BLOCK 16
+
+#define SM0_ODRAIN BIT(31)
+#define SM0_VSYNC_MODE BIT(28)
+#define SM0_CLK_DIV (CLKDIV_VALUE << 16)
+#define SM0_WAIT_LEVEL BIT(6)
+#define SM0_EN BIT(1)
+
+#define SM0_CFG_DEFUALT (SM0_ODRAIN | SM0_VSYNC_MODE | \
+ SM0_CLK_DIV | SM0_WAIT_LEVEL | \
+ SM0_EN)
+/***********************************************************/
+
+static void __iomem *membase;
+static struct i2c_adapter *adapter;
+
+static void rt_i2c_w32(u32 val, unsigned reg)
+static void mtk_i2c_w32(struct mtk_i2c *i2c, u32 val, unsigned reg)
+{
+ iowrite32(val, membase + reg);
+ iowrite32(val, i2c->base + reg);
+}
+
+static u32 rt_i2c_r32(unsigned reg)
+static u32 mtk_i2c_r32(struct mtk_i2c *i2c, unsigned reg)
+{
+ return ioread32(membase + reg);
+ return ioread32(i2c->base + reg);
+}
+
+static void mt7621_i2c_reset(struct i2c_adapter *a)
+static int poll_down_timeout(void __iomem *addr, u32 mask)
+{
+ device_reset(a->dev.parent);
+ unsigned long timeout = jiffies + msecs_to_jiffies(TIMEOUT_MS);
+
+ do {
+ if (!(readl_relaxed(addr) & mask))
+ return 0;
+
+ usleep_range(DELAY_INTERVAL_US, DELAY_INTERVAL_US + 50);
+ } while (time_before(jiffies, timeout));
+
+ return (readl_relaxed(addr) & mask) ? -EAGAIN : 0;
+}
+static void mt7621_i2c_enable(struct i2c_msg *msg)
+
+static int mtk_i2c_wait_idle(struct mtk_i2c *i2c)
+{
+ rt_i2c_w32(msg->addr,REG_DEVADDR_REG);
+ rt_i2c_w32(0,REG_ADDR_REG);
+ int ret;
+
+ ret = poll_down_timeout(i2c->base + REG_SM0ST, I2C_BUSY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "idle err(%d)\n", ret);
+
+ return ret;
+}
+
+static void i2c_master_init(struct i2c_adapter *a)
+static int poll_up_timeout(void __iomem *addr, u32 mask)
+{
+ mt7621_i2c_reset(a);
+ rt_i2c_w32(I2C_CFG_DEFAULT,REG_CONFIG_REG);
+ rt_i2c_w32(SM0_CFG_DEFUALT,REG_SM0CTL0);
+ rt_i2c_w32(1,REG_SM0_IS_AUTOMODE);//auto mode
+}
+ unsigned long timeout = jiffies + msecs_to_jiffies(TIMEOUT_MS);
+ u32 status;
+
+ do {
+ status = readl_relaxed(addr);
+ if (status & mask)
+ return 0;
+ usleep_range(DELAY_INTERVAL_US, DELAY_INTERVAL_US + 50);
+ } while (time_before(jiffies, timeout));
+
+static inline int rt_i2c_wait_rx_done(void)
+{
+ int i=0;
+ while((!(rt_i2c_r32(REG_STATUS_REG) & I2C_DATARDY)) && (i<i2c_busy_loop))
+ i++;
+ if(i>=i2c_busy_loop){
+ pr_err("err,wait for idle timeout");
+ return -ETIMEDOUT;
+ }
+ return 0;
+ return -ETIMEDOUT;
+}
+
+static inline int rt_i2c_wait_idle(void)
+static int mtk_i2c_wait_rx_done(struct mtk_i2c *i2c)
+{
+ int i=0;
+ while((rt_i2c_r32(REG_STATUS_REG) & I2C_BUSY) && (i<i2c_busy_loop))
+ i++;
+ if(i>=i2c_busy_loop){
+ pr_err("err,wait for idle timeout");
+ return -ETIMEDOUT;
+ }
+ return 0;
+ int ret;
+
+ ret = poll_up_timeout(i2c->base + REG_SM0ST, I2C_DATARDY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "rx err(%d)\n", ret);
+
+ return ret;
+}
+
+static inline int rt_i2c_wait_tx_done(void)
+static int mtk_i2c_wait_tx_done(struct mtk_i2c *i2c)
+{
+ int i=0;
+ while((!(rt_i2c_r32(REG_STATUS_REG) & I2C_SDOEMPTY)) && (i<i2c_busy_loop))
+ i++;
+ if(i>=i2c_busy_loop){
+ pr_err("err,wait for idle timeout");
+ return -ETIMEDOUT;
+ }
+ return 0;
+ int ret;
+
+ ret = poll_up_timeout(i2c->base + REG_SM0ST, I2C_SDOEMPTY);
+ if (ret < 0)
+ dev_dbg(i2c->dev, "tx err(%d)\n", ret);
+
+ return ret;
+}
+
+static int rt_i2c_handle_msg(struct i2c_adapter *a, struct i2c_msg* msg)
+static void mtk_i2c_reset(struct mtk_i2c *i2c)
+{
+ int i = 0, j = 0, pos = 0;
+ int nblock = msg->len / READ_BLOCK;
+ int rem = msg->len % READ_BLOCK;
+ u32 reg;
+ device_reset(i2c->adap.dev.parent);
+ barrier();
+
+ if (msg->flags & I2C_M_TEN) {
+ printk("10 bits addr not supported\n");
+ return -EINVAL;
+ }
+ /* ctrl0 */
+ reg = ODRAIN_HIGH_SM0 | VSYNC_PULSE | (i2c->clk_div << CLK_DIV_SHIFT) |
+ WAIT_HIGH | SM0_EN;
+ mtk_i2c_w32(i2c, reg, REG_SM0CTL0);
+
+ if (msg->flags & I2C_M_RD) {
+ for (i = 0; i < nblock; i++) {
+ if (rt_i2c_wait_idle())
+ goto err_timeout;
+ rt_i2c_w32(READ_BLOCK - 1, REG_BYTECNT_REG);
+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
+ for (j = 0; j < READ_BLOCK; j++) {
+ if (rt_i2c_wait_rx_done())
+ goto err_timeout;
+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
+ }
+ }
+ /* auto mode */
+ mtk_i2c_w32(i2c, AUTOMODE_EN, REG_SM0CFG2);
+}
+
+static void mtk_i2c_dump_reg(struct mtk_i2c *i2c)
+{
+ dev_dbg(i2c->dev, "cfg0 %08x, dout %08x, din %08x, " \
+ "status %08x, auto %08x, cfg1 %08x, " \
+ "cfg2 %08x, ctl0 %08x, ctl1 %08x\n",
+ mtk_i2c_r32(i2c, REG_SM0CFG0),
+ mtk_i2c_r32(i2c, REG_SM0DOUT),
+ mtk_i2c_r32(i2c, REG_SM0DIN),
+ mtk_i2c_r32(i2c, REG_SM0ST),
+ mtk_i2c_r32(i2c, REG_SM0AUTO),
+ mtk_i2c_r32(i2c, REG_SM0CFG1),
+ mtk_i2c_r32(i2c, REG_SM0CFG2),
+ mtk_i2c_r32(i2c, REG_SM0CTL0),
+ mtk_i2c_r32(i2c, REG_SM0CTL1));
+}
+
+ if (rt_i2c_wait_idle())
+ goto err_timeout;
+ rt_i2c_w32(rem - 1, REG_BYTECNT_REG);
+ rt_i2c_w32(READ_CMD, REG_STARTXFR_REG);
+
+ for (i = 0; i < rem; i++) {
+ if (rt_i2c_wait_rx_done())
+ goto err_timeout;
+ msg->buf[pos++] = rt_i2c_r32(REG_DATAIN_REG);
+static int mtk_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ struct mtk_i2c *i2c;
+ struct i2c_msg *pmsg;
+ int i, j, ret;
+ u32 cmd;
+
+ i2c = i2c_get_adapdata(adap);
+
+ for (i = 0; i < num; i++) {
+ pmsg = &msgs[i];
+ cmd = 0;
+
+ dev_dbg(i2c->dev, "addr: 0x%x, len: %d, flags: 0x%x\n",
+ pmsg->addr, pmsg->len, pmsg->flags);
+
+ /* wait hardware idle */
+ if ((ret = mtk_i2c_wait_idle(i2c)))
+ goto err_timeout;
+
+ if (pmsg->flags & I2C_M_TEN) {
+ dev_dbg(i2c->dev, "10 bits addr not supported\n");
+ return -EINVAL;
+ } else {
+ /* 7 bits address */
+ mtk_i2c_w32(i2c, pmsg->addr & I2C_DEVADDR_MASK,
+ REG_SM0CFG0);
+ }
+ } else {
+ if (rt_i2c_wait_idle())
+ goto err_timeout;
+ rt_i2c_w32(msg->len - 1, REG_BYTECNT_REG);
+ for (i = 0; i < msg->len; i++) {
+ rt_i2c_w32(msg->buf[i], REG_DATAOUT_REG);
+ if(i == 0)
+ rt_i2c_w32(WRITE_CMD, REG_STARTXFR_REG);
+
+ if (rt_i2c_wait_tx_done())
+ goto err_timeout;
+
+ /* buffer length */
+ if (pmsg->len == 0) {
+ dev_dbg(i2c->dev, "length is 0\n");
+ return -EINVAL;
+ } else
+ mtk_i2c_w32(i2c, SET_BYTECNT(pmsg->len),
+ REG_SM0CFG1);
+
+ j = 0;
+ if (pmsg->flags & I2C_M_RD) {
+ cmd |= READ_CMD;
+ /* start transfer */
+ barrier();
+ mtk_i2c_w32(i2c, cmd, REG_SM0AUTO);
+ do {
+ /* wait */
+ if ((ret = mtk_i2c_wait_rx_done(i2c)))
+ goto err_timeout;
+ /* read data */
+ if (pmsg->len)
+ pmsg->buf[j] = mtk_i2c_r32(i2c,
+ REG_SM0DIN);
+ j++;
+ } while (j < pmsg->len);
+ } else {
+ do {
+ /* write data */
+ if (pmsg->len)
+ mtk_i2c_w32(i2c, pmsg->buf[j],
+ REG_SM0DOUT);
+ /* start transfer */
+ if (j == 0) {
+ barrier();
+ mtk_i2c_w32(i2c, cmd, REG_SM0AUTO);
+ }
+ /* wait */
+ if ((ret = mtk_i2c_wait_tx_done(i2c)))
+ goto err_timeout;
+ j++;
+ } while (j < pmsg->len);
+ }
+ }
+ /* the return value is number of executed messages */
+ ret = i;
+
+ return 0;
+err_timeout:
+ return -ETIMEDOUT;
+}
+ return ret;
+
+static int rt_i2c_master_xfer(struct i2c_adapter *a, struct i2c_msg *m, int n)
+{
+ int i = 0;
+ int ret = 0;
+ i2c_master_init(a);
+ mt7621_i2c_enable(m);
+
+ for (i = 0; i != n && ret==0; i++) {
+ ret = rt_i2c_handle_msg(a, &m[i]);
+ if (ret)
+ return ret;
+ }
+ return i;
+err_timeout:
+ mtk_i2c_dump_reg(i2c);
+ mtk_i2c_reset(i2c);
+ return ret;
+}
+
+static u32 rt_i2c_func(struct i2c_adapter *a)
+static u32 mtk_i2c_func(struct i2c_adapter *a)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm rt_i2c_algo = {
+ .master_xfer = rt_i2c_master_xfer,
+ .functionality = rt_i2c_func,
+static const struct i2c_algorithm mtk_i2c_algo = {
+ .master_xfer = mtk_i2c_master_xfer,
+ .functionality = mtk_i2c_func,
+};
+
+static int rt_i2c_probe(struct platform_device *pdev)
+static const struct of_device_id i2c_mtk_dt_ids[] = {
+ { .compatible = "mediatek,mt7621-i2c" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, i2c_mtk_dt_ids);
+
+static struct i2c_adapter_quirks mtk_i2c_quirks = {
+ .max_write_len = BYTECNT_MAX,
+ .max_read_len = BYTECNT_MAX,
+};
+
+static void mtk_i2c_init(struct mtk_i2c *i2c)
+{
+ i2c->clk_div = clk_get_rate(i2c->clk) / i2c->cur_clk;
+ if (i2c->clk_div > CLK_DIV_MASK)
+ i2c->clk_div = CLK_DIV_MASK;
+
+ mtk_i2c_reset(i2c);
+}
+
+static int mtk_i2c_probe(struct platform_device *pdev)
+{
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ struct resource *res;
+ struct mtk_i2c *i2c;
+ struct i2c_adapter *adap;
+ const struct of_device_id *match;
+ int ret;
+
+ adapter = devm_kzalloc(&pdev->dev,sizeof(struct i2c_adapter), GFP_KERNEL);
+ if (!adapter) {
+ match = of_match_device(i2c_mtk_dt_ids, &pdev->dev);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no memory resource found\n");
+ return -ENODEV;
+ }
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(struct mtk_i2c), GFP_KERNEL);
+ if (!i2c) {
+ dev_err(&pdev->dev, "failed to allocate i2c_adapter\n");
+ return -ENOMEM;
+ }
+ membase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(membase))
+ return PTR_ERR(membase);
+
+ strlcpy(adapter->name, dev_name(&pdev->dev), sizeof(adapter->name));
+
+ adapter->owner = THIS_MODULE;
+ adapter->nr = pdev->id;
+ adapter->timeout = HZ;
+ adapter->algo = &rt_i2c_algo;
+ adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adapter->dev.parent = &pdev->dev;
+ adapter->dev.of_node = pdev->dev.of_node;
+
+ platform_set_drvdata(pdev, adapter);
+
+ ret = i2c_add_numbered_adapter(adapter);
+ if (ret)
+
+ i2c->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(i2c->base))
+ return PTR_ERR(i2c->base);
+
+ i2c->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c->clk)) {
+ dev_err(&pdev->dev, "no clock defined\n");
+ return -ENODEV;
+ }
+ clk_prepare_enable(i2c->clk);
+ i2c->dev = &pdev->dev;
+
+ if (of_property_read_u32(pdev->dev.of_node,
+ "clock-frequency", &i2c->cur_clk))
+ i2c->cur_clk = 100000;
+
+ adap = &i2c->adap;
+ adap->owner = THIS_MODULE;
+ adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adap->algo = &mtk_i2c_algo;
+ adap->retries = 3;
+ adap->dev.parent = &pdev->dev;
+ i2c_set_adapdata(adap, i2c);
+ adap->dev.of_node = pdev->dev.of_node;
+ strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
+ adap->quirks = &mtk_i2c_quirks;
+
+ platform_set_drvdata(pdev, i2c);
+
+ mtk_i2c_init(i2c);
+
+ ret = i2c_add_adapter(adap);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add adapter\n");
+ clk_disable_unprepare(i2c->clk);
+ return ret;
+ }
+
+ dev_info(&pdev->dev,"loaded");
+ dev_info(&pdev->dev, "clock %uKHz, re-start not support\n",
+ i2c->cur_clk/1000);
+
+ return 0;
+ return ret;
+}
+
+static int rt_i2c_remove(struct platform_device *pdev)
+static int mtk_i2c_remove(struct platform_device *pdev)
+{
+ platform_set_drvdata(pdev, NULL);
+ return 0;
+}
+ struct mtk_i2c *i2c = platform_get_drvdata(pdev);
+
+static const struct of_device_id i2c_rt_dt_ids[] = {
+ { .compatible = "ralink,i2c-mt7621", },
+ { /* sentinel */ }
+};
+ i2c_del_adapter(&i2c->adap);
+ clk_disable_unprepare(i2c->clk);
+
+MODULE_DEVICE_TABLE(of, i2c_rt_dt_ids);
+ return 0;
+}
+
+static struct platform_driver rt_i2c_driver = {
+ .probe = rt_i2c_probe,
+ .remove = rt_i2c_remove,
+static struct platform_driver mtk_i2c_driver = {
+ .probe = mtk_i2c_probe,
+ .remove = mtk_i2c_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "i2c-mt7621",
+ .of_match_table = i2c_rt_dt_ids,
+ .of_match_table = i2c_mtk_dt_ids,
+ },
+};
+
+static int __init i2c_rt_init (void)
+static int __init i2c_mtk_init (void)
+{
+ return platform_driver_register(&rt_i2c_driver);
+ return platform_driver_register(&mtk_i2c_driver);
+}
+subsys_initcall(i2c_mtk_init);
+
+static void __exit i2c_rt_exit (void)
+static void __exit i2c_mtk_exit (void)
+{
+ platform_driver_unregister(&rt_i2c_driver);
+ platform_driver_unregister(&mtk_i2c_driver);
+}
+module_init (i2c_rt_init);
+module_exit (i2c_rt_exit);
+module_exit(i2c_mtk_exit);
+
+MODULE_AUTHOR("Steven Liu <steven_liu@mediatek.com>");
+MODULE_DESCRIPTION("MT7621 I2c host driver");

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