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path: root/drivers/i2c/busses/i2c-uniphier-f.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-uniphier-f.c')
-rw-r--r--drivers/i2c/busses/i2c-uniphier-f.c106
1 files changed, 51 insertions, 55 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c
index aeead0d27d10..db9105e52c79 100644
--- a/drivers/i2c/busses/i2c-uniphier-f.c
+++ b/drivers/i2c/busses/i2c-uniphier-f.c
@@ -14,6 +14,7 @@
#include <linux/clk.h>
#include <linux/i2c.h>
+#include <linux/iopoll.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
@@ -348,14 +349,19 @@ static int uniphier_fi2c_master_xfer_one(struct i2c_adapter *adap,
dev_dbg(&adap->dev, "complete\n");
if (unlikely(priv->flags & UNIPHIER_FI2C_DEFER_STOP_COMP)) {
- u32 status = readl(priv->membase + UNIPHIER_FI2C_SR);
-
- if (!(status & UNIPHIER_FI2C_SR_STS) ||
- status & UNIPHIER_FI2C_SR_BB) {
+ u32 status;
+ int ret;
+
+ ret = readl_poll_timeout(priv->membase + UNIPHIER_FI2C_SR,
+ status,
+ (status & UNIPHIER_FI2C_SR_STS) &&
+ !(status & UNIPHIER_FI2C_SR_BB),
+ 1, 20);
+ if (ret) {
dev_err(&adap->dev,
"stop condition was not completed.\n");
uniphier_fi2c_recover(priv);
- return -EBUSY;
+ return ret;
}
}
@@ -455,54 +461,25 @@ static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = {
.unprepare_recovery = uniphier_fi2c_unprepare_recovery,
};
-static int uniphier_fi2c_clk_init(struct device *dev,
- struct uniphier_fi2c_priv *priv)
+static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv,
+ u32 bus_speed, unsigned long clk_rate)
{
- struct device_node *np = dev->of_node;
- unsigned long clk_rate;
- u32 bus_speed, clk_count;
- int ret;
-
- if (of_property_read_u32(np, "clock-frequency", &bus_speed))
- bus_speed = UNIPHIER_FI2C_DEFAULT_SPEED;
-
- if (!bus_speed) {
- dev_err(dev, "clock-frequency should not be zero\n");
- return -EINVAL;
- }
-
- if (bus_speed > UNIPHIER_FI2C_MAX_SPEED)
- bus_speed = UNIPHIER_FI2C_MAX_SPEED;
-
- /* Get input clk rate through clk driver */
- priv->clk = devm_clk_get(dev, NULL);
- if (IS_ERR(priv->clk)) {
- dev_err(dev, "failed to get clock\n");
- return PTR_ERR(priv->clk);
- }
+ u32 tmp;
- ret = clk_prepare_enable(priv->clk);
- if (ret)
- return ret;
-
- clk_rate = clk_get_rate(priv->clk);
- if (!clk_rate) {
- dev_err(dev, "input clock rate should not be zero\n");
- return -EINVAL;
- }
+ tmp = readl(priv->membase + UNIPHIER_FI2C_CR);
+ tmp |= UNIPHIER_FI2C_CR_MST;
+ writel(tmp, priv->membase + UNIPHIER_FI2C_CR);
uniphier_fi2c_reset(priv);
- clk_count = clk_rate / bus_speed;
+ tmp = clk_rate / bus_speed;
- writel(clk_count, priv->membase + UNIPHIER_FI2C_CYC);
- writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_LCTL);
- writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_SSUT);
- writel(clk_count / 16, priv->membase + UNIPHIER_FI2C_DSUT);
+ writel(tmp, priv->membase + UNIPHIER_FI2C_CYC);
+ writel(tmp / 2, priv->membase + UNIPHIER_FI2C_LCTL);
+ writel(tmp / 2, priv->membase + UNIPHIER_FI2C_SSUT);
+ writel(tmp / 16, priv->membase + UNIPHIER_FI2C_DSUT);
uniphier_fi2c_prepare_operation(priv);
-
- return 0;
}
static int uniphier_fi2c_probe(struct platform_device *pdev)
@@ -510,8 +487,9 @@ static int uniphier_fi2c_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct uniphier_fi2c_priv *priv;
struct resource *regs;
- int irq;
- int ret;
+ u32 bus_speed;
+ unsigned long clk_rate;
+ int irq, ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -528,6 +506,31 @@ static int uniphier_fi2c_probe(struct platform_device *pdev)
return irq;
}
+ if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed))
+ bus_speed = UNIPHIER_FI2C_DEFAULT_SPEED;
+
+ if (!bus_speed || bus_speed > UNIPHIER_FI2C_MAX_SPEED) {
+ dev_err(dev, "invalid clock-frequency %d\n", bus_speed);
+ return -EINVAL;
+ }
+
+ priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk)) {
+ dev_err(dev, "failed to get clock\n");
+ return PTR_ERR(priv->clk);
+ }
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ return ret;
+
+ clk_rate = clk_get_rate(priv->clk);
+ if (!clk_rate) {
+ dev_err(dev, "input clock rate should not be zero\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
init_completion(&priv->comp);
priv->adap.owner = THIS_MODULE;
priv->adap.algo = &uniphier_fi2c_algo;
@@ -538,9 +541,7 @@ static int uniphier_fi2c_probe(struct platform_device *pdev)
i2c_set_adapdata(&priv->adap, priv);
platform_set_drvdata(pdev, priv);
- ret = uniphier_fi2c_clk_init(dev, priv);
- if (ret)
- goto err;
+ uniphier_fi2c_hw_init(priv, bus_speed, clk_rate);
ret = devm_request_irq(dev, irq, uniphier_fi2c_interrupt, 0,
pdev->name, priv);
@@ -550,11 +551,6 @@ static int uniphier_fi2c_probe(struct platform_device *pdev)
}
ret = i2c_add_adapter(&priv->adap);
- if (ret) {
- dev_err(dev, "failed to add I2C adapter\n");
- goto err;
- }
-
err:
if (ret)
clk_disable_unprepare(priv->clk);