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Diffstat (limited to 'drivers/i2c/busses/i2c-sh_mobile.c')
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c225
1 files changed, 107 insertions, 118 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 1d79585ba4b3..8b5e79cb4468 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -32,6 +32,7 @@
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/of_device.h>
#include <linux/i2c/i2c-sh_mobile.h>
/* Transmit operation: */
@@ -139,6 +140,10 @@ struct sh_mobile_i2c_data {
bool send_stop;
};
+struct sh_mobile_dt_config {
+ int clks_per_count;
+};
+
#define IIC_FLAG_HAS_ICIC67 (1 << 0)
#define STANDARD_MODE 100000
@@ -194,7 +199,7 @@ static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs,
iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr);
}
-static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int offset)
+static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf)
{
/*
* Conditional expression:
@@ -206,10 +211,10 @@ static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int off
* account the fall time of SCL signal (tf). Default tf value
* should be 0.3 us, for safety.
*/
- return (((count_khz * (tLOW + tf)) + 5000) / 10000) + offset;
+ return (((count_khz * (tLOW + tf)) + 5000) / 10000);
}
-static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int offset)
+static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf)
{
/*
* Conditional expression:
@@ -225,52 +230,58 @@ static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int of
* to take into account the fall time of SDA signal (tf) at START
* condition, in order to meet both tHIGH and tHD;STA specs.
*/
- return (((count_khz * (tHIGH + tf)) + 5000) / 10000) + offset;
+ return (((count_khz * (tHIGH + tf)) + 5000) / 10000);
}
-static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)
+static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)
{
unsigned long i2c_clk_khz;
u32 tHIGH, tLOW, tf;
- int offset;
+ uint16_t max_val;
/* Get clock rate after clock is enabled */
clk_prepare_enable(pd->clk);
i2c_clk_khz = clk_get_rate(pd->clk) / 1000;
+ clk_disable_unprepare(pd->clk);
i2c_clk_khz /= pd->clks_per_count;
if (pd->bus_speed == STANDARD_MODE) {
tLOW = 47; /* tLOW = 4.7 us */
tHIGH = 40; /* tHD;STA = tHIGH = 4.0 us */
tf = 3; /* tf = 0.3 us */
- offset = 0; /* No offset */
} else if (pd->bus_speed == FAST_MODE) {
tLOW = 13; /* tLOW = 1.3 us */
tHIGH = 6; /* tHD;STA = tHIGH = 0.6 us */
tf = 3; /* tf = 0.3 us */
- offset = 0; /* No offset */
} else {
dev_err(pd->dev, "unrecognized bus speed %lu Hz\n",
pd->bus_speed);
- goto out;
+ return -EINVAL;
+ }
+
+ pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf);
+ pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf);
+
+ max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff;
+ if (pd->iccl > max_val || pd->icch > max_val) {
+ dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n",
+ pd->iccl, pd->icch);
+ return -EINVAL;
}
- pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf, offset);
/* one more bit of ICCL in ICIC */
- if ((pd->iccl > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67))
+ if (pd->iccl & 0x100)
pd->icic |= ICIC_ICCLB8;
else
pd->icic &= ~ICIC_ICCLB8;
- pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf, offset);
/* one more bit of ICCH in ICIC */
- if ((pd->icch > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67))
+ if (pd->icch & 0x100)
pd->icic |= ICIC_ICCHB8;
else
pd->icic &= ~ICIC_ICCHB8;
-out:
- clk_disable_unprepare(pd->clk);
+ return 0;
}
static void activate_ch(struct sh_mobile_i2c_data *pd)
@@ -316,7 +327,7 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
switch (op) {
case OP_START: /* issue start and trigger DTE interrupt */
- iic_wr(pd, ICCR, 0x94);
+ iic_wr(pd, ICCR, ICCR_ICE | ICCR_TRS | ICCR_BBSY);
break;
case OP_TX_FIRST: /* disable DTE interrupt and write data */
iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
@@ -327,10 +338,11 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
break;
case OP_TX_STOP: /* write data and issue a stop afterwards */
iic_wr(pd, ICDR, data);
- iic_wr(pd, ICCR, pd->send_stop ? 0x90 : 0x94);
+ iic_wr(pd, ICCR, pd->send_stop ? ICCR_ICE | ICCR_TRS
+ : ICCR_ICE | ICCR_TRS | ICCR_BBSY);
break;
case OP_TX_TO_RX: /* select read mode */
- iic_wr(pd, ICCR, 0x81);
+ iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP);
break;
case OP_RX: /* just read data */
ret = iic_rd(pd, ICDR);
@@ -338,13 +350,13 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
case OP_RX_STOP: /* enable DTE interrupt, issue stop */
iic_wr(pd, ICIC,
ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
- iic_wr(pd, ICCR, 0xc0);
+ iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK);
break;
case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */
iic_wr(pd, ICIC,
ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
ret = iic_rd(pd, ICDR);
- iic_wr(pd, ICCR, 0xc0);
+ iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK);
break;
}
@@ -479,7 +491,7 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg,
{
if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) {
dev_err(pd->dev, "Unsupported zero length i2c read\n");
- return -EIO;
+ return -EOPNOTSUPP;
}
if (do_init) {
@@ -514,17 +526,12 @@ static int poll_dte(struct sh_mobile_i2c_data *pd)
break;
if (val & ICSR_TACK)
- return -EIO;
+ return -ENXIO;
udelay(10);
}
- if (!i) {
- dev_warn(pd->dev, "Timeout polling for DTE!\n");
- return -ETIMEDOUT;
- }
-
- return 0;
+ return i ? 0 : -ETIMEDOUT;
}
static int poll_busy(struct sh_mobile_i2c_data *pd)
@@ -542,20 +549,18 @@ static int poll_busy(struct sh_mobile_i2c_data *pd)
*/
if (!(val & ICSR_BUSY)) {
/* handle missing acknowledge and arbitration lost */
- if ((val | pd->sr) & (ICSR_TACK | ICSR_AL))
- return -EIO;
+ val |= pd->sr;
+ if (val & ICSR_TACK)
+ return -ENXIO;
+ if (val & ICSR_AL)
+ return -EAGAIN;
break;
}
udelay(10);
}
- if (!i) {
- dev_err(pd->dev, "Polling timed out\n");
- return -ETIMEDOUT;
- }
-
- return 0;
+ return i ? 0 : -ETIMEDOUT;
}
static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
@@ -617,42 +622,44 @@ static struct i2c_algorithm sh_mobile_i2c_algorithm = {
.master_xfer = sh_mobile_i2c_xfer,
};
-static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook)
+static const struct sh_mobile_dt_config default_dt_config = {
+ .clks_per_count = 1,
+};
+
+static const struct sh_mobile_dt_config rcar_gen2_dt_config = {
+ .clks_per_count = 2,
+};
+
+static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
+ { .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
+ { .compatible = "renesas,iic-r8a7790", .data = &rcar_gen2_dt_config },
+ { .compatible = "renesas,iic-r8a7791", .data = &rcar_gen2_dt_config },
+ { .compatible = "renesas,iic-r8a7792", .data = &rcar_gen2_dt_config },
+ { .compatible = "renesas,iic-r8a7793", .data = &rcar_gen2_dt_config },
+ { .compatible = "renesas,iic-r8a7794", .data = &rcar_gen2_dt_config },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids);
+
+static int sh_mobile_i2c_hook_irqs(struct platform_device *dev)
{
struct resource *res;
- int ret = -ENXIO;
- int n, k = 0;
+ resource_size_t n;
+ int k = 0, ret;
while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) {
- for (n = res->start; hook && n <= res->end; n++) {
- if (request_irq(n, sh_mobile_i2c_isr, 0,
- dev_name(&dev->dev), dev)) {
- for (n--; n >= res->start; n--)
- free_irq(n, dev);
-
- goto rollback;
+ for (n = res->start; n <= res->end; n++) {
+ ret = devm_request_irq(&dev->dev, n, sh_mobile_i2c_isr,
+ 0, dev_name(&dev->dev), dev);
+ if (ret) {
+ dev_err(&dev->dev, "cannot request IRQ %pa\n", &n);
+ return ret;
}
}
k++;
}
- if (hook)
- return k > 0 ? 0 : -ENOENT;
-
- ret = 0;
-
- rollback:
- k--;
-
- while (k >= 0) {
- res = platform_get_resource(dev, IORESOURCE_IRQ, k);
- for (n = res->start; n <= res->end; n++)
- free_irq(n, dev);
-
- k--;
- }
-
- return ret;
+ return k > 0 ? 0 : -ENOENT;
}
static int sh_mobile_i2c_probe(struct platform_device *dev)
@@ -661,62 +668,64 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
struct sh_mobile_i2c_data *pd;
struct i2c_adapter *adap;
struct resource *res;
- int size;
int ret;
+ u32 bus_speed;
- pd = kzalloc(sizeof(struct sh_mobile_i2c_data), GFP_KERNEL);
- if (pd == NULL) {
- dev_err(&dev->dev, "cannot allocate private data\n");
+ pd = devm_kzalloc(&dev->dev, sizeof(struct sh_mobile_i2c_data), GFP_KERNEL);
+ if (!pd)
return -ENOMEM;
- }
- pd->clk = clk_get(&dev->dev, NULL);
+ pd->clk = devm_clk_get(&dev->dev, NULL);
if (IS_ERR(pd->clk)) {
dev_err(&dev->dev, "cannot get clock\n");
- ret = PTR_ERR(pd->clk);
- goto err;
+ return PTR_ERR(pd->clk);
}
- ret = sh_mobile_i2c_hook_irqs(dev, 1);
- if (ret) {
- dev_err(&dev->dev, "cannot request IRQ\n");
- goto err_clk;
- }
+ ret = sh_mobile_i2c_hook_irqs(dev);
+ if (ret)
+ return ret;
pd->dev = &dev->dev;
platform_set_drvdata(dev, pd);
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
- if (res == NULL) {
- dev_err(&dev->dev, "cannot find IO resource\n");
- ret = -ENOENT;
- goto err_irq;
- }
-
- size = resource_size(res);
- pd->reg = ioremap(res->start, size);
- if (pd->reg == NULL) {
- dev_err(&dev->dev, "cannot map IO\n");
- ret = -ENXIO;
- goto err_irq;
- }
+ pd->reg = devm_ioremap_resource(&dev->dev, res);
+ if (IS_ERR(pd->reg))
+ return PTR_ERR(pd->reg);
/* Use platform data bus speed or STANDARD_MODE */
- pd->bus_speed = STANDARD_MODE;
- if (pdata && pdata->bus_speed)
- pd->bus_speed = pdata->bus_speed;
+ ret = of_property_read_u32(dev->dev.of_node, "clock-frequency", &bus_speed);
+ pd->bus_speed = ret ? STANDARD_MODE : bus_speed;
+
pd->clks_per_count = 1;
- if (pdata && pdata->clks_per_count)
- pd->clks_per_count = pdata->clks_per_count;
+
+ if (dev->dev.of_node) {
+ const struct of_device_id *match;
+
+ match = of_match_device(sh_mobile_i2c_dt_ids, &dev->dev);
+ if (match) {
+ const struct sh_mobile_dt_config *config;
+
+ config = match->data;
+ pd->clks_per_count = config->clks_per_count;
+ }
+ } else {
+ if (pdata && pdata->bus_speed)
+ pd->bus_speed = pdata->bus_speed;
+ if (pdata && pdata->clks_per_count)
+ pd->clks_per_count = pdata->clks_per_count;
+ }
/* The IIC blocks on SH-Mobile ARM processors
* come with two new bits in ICIC.
*/
- if (size > 0x17)
+ if (resource_size(res) > 0x17)
pd->flags |= IIC_FLAG_HAS_ICIC67;
- sh_mobile_i2c_init(pd);
+ ret = sh_mobile_i2c_init(pd);
+ if (ret)
+ return ret;
/* Enable Runtime PM for this device.
*
@@ -750,24 +759,14 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
ret = i2c_add_numbered_adapter(adap);
if (ret < 0) {
dev_err(&dev->dev, "cannot add numbered adapter\n");
- goto err_all;
+ return ret;
}
dev_info(&dev->dev,
- "I2C adapter %d with bus speed %lu Hz (L/H=%x/%x)\n",
+ "I2C adapter %d with bus speed %lu Hz (L/H=0x%x/0x%x)\n",
adap->nr, pd->bus_speed, pd->iccl, pd->icch);
return 0;
-
- err_all:
- iounmap(pd->reg);
- err_irq:
- sh_mobile_i2c_hook_irqs(dev, 0);
- err_clk:
- clk_put(pd->clk);
- err:
- kfree(pd);
- return ret;
}
static int sh_mobile_i2c_remove(struct platform_device *dev)
@@ -775,11 +774,7 @@ static int sh_mobile_i2c_remove(struct platform_device *dev)
struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev);
i2c_del_adapter(&pd->adap);
- iounmap(pd->reg);
- sh_mobile_i2c_hook_irqs(dev, 0);
- clk_put(pd->clk);
pm_runtime_disable(&dev->dev);
- kfree(pd);
return 0;
}
@@ -800,12 +795,6 @@ static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = {
.runtime_resume = sh_mobile_i2c_runtime_nop,
};
-static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
- { .compatible = "renesas,rmobile-iic", },
- {},
-};
-MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids);
-
static struct platform_driver sh_mobile_i2c_driver = {
.driver = {
.name = "i2c-sh_mobile",