+};
--- 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
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>
+#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
+#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)
+};
+
+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;
+}
+{
+ 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");
projects / librecmc / librecmc.git / blobdiff