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Diffstat (limited to 'drivers/i2c/busses/i2c-nomadik.c')
-rw-r--r--drivers/i2c/busses/i2c-nomadik.c286
1 files changed, 140 insertions, 146 deletions
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 512dfe60970..0e55d85fd4e 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -22,9 +22,7 @@
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
-#include <linux/platform_data/i2c-nomadik.h>
#include <linux/of.h>
-#include <linux/of_i2c.h>
#include <linux/pinctrl/consumer.h>
#define DRIVER_NAME "nmk-i2c"
@@ -105,6 +103,13 @@
/* maximum threshold value */
#define MAX_I2C_FIFO_THRESHOLD 15
+enum i2c_freq_mode {
+ I2C_FREQ_MODE_STANDARD, /* up to 100 Kb/s */
+ I2C_FREQ_MODE_FAST, /* up to 400 Kb/s */
+ I2C_FREQ_MODE_HIGH_SPEED, /* up to 3.4 Mb/s */
+ I2C_FREQ_MODE_FAST_PLUS, /* up to 1 Mb/s */
+};
+
/**
* struct i2c_vendor_data - per-vendor variations
* @has_mtdws: variant has the MTDWS bit
@@ -153,12 +158,15 @@ struct i2c_nmk_client {
* @irq: interrupt line for the controller.
* @virtbase: virtual io memory area.
* @clk: hardware i2c block clock.
- * @cfg: machine provided controller configuration.
* @cli: holder of client specific data.
+ * @clk_freq: clock frequency for the operation mode
+ * @tft: Tx FIFO Threshold in bytes
+ * @rft: Rx FIFO Threshold in bytes
+ * @timeout Slave response timeout (ms)
+ * @sm: speed mode
* @stop: stop condition.
* @xfer_complete: acknowledge completion for a I2C message.
* @result: controller propogated result.
- * @busy: Busy doing transfer.
*/
struct nmk_i2c_dev {
struct i2c_vendor_data *vendor;
@@ -167,12 +175,15 @@ struct nmk_i2c_dev {
int irq;
void __iomem *virtbase;
struct clk *clk;
- struct nmk_i2c_controller cfg;
struct i2c_nmk_client cli;
+ u32 clk_freq;
+ unsigned char tft;
+ unsigned char rft;
+ int timeout;
+ enum i2c_freq_mode sm;
int stop;
struct completion xfer_complete;
int result;
- bool busy;
};
/* controller's abort causes */
@@ -341,6 +352,8 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
{
u32 brcr1, brcr2;
u32 i2c_clk, div;
+ u32 ns;
+ u16 slsu;
writel(0x0, dev->virtbase + I2C_CR);
writel(0x0, dev->virtbase + I2C_HSMCR);
@@ -348,25 +361,45 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
writel(0x0, dev->virtbase + I2C_RFTR);
writel(0x0, dev->virtbase + I2C_DMAR);
+ i2c_clk = clk_get_rate(dev->clk);
+
/*
* set the slsu:
*
* slsu defines the data setup time after SCL clock
- * stretching in terms of i2c clk cycles. The
- * needed setup time for the three modes are 250ns,
- * 100ns, 10ns respectively thus leading to the values
- * of 14, 6, 2 for a 48 MHz i2c clk.
+ * stretching in terms of i2c clk cycles + 1 (zero means
+ * "wait one cycle"), the needed setup time for the three
+ * modes are 250ns, 100ns, 10ns respectively.
+ *
+ * As the time for one cycle T in nanoseconds is
+ * T = (1/f) * 1000000000 =>
+ * slsu = cycles / (1000000000 / f) + 1
*/
- writel(dev->cfg.slsu << 16, dev->virtbase + I2C_SCR);
+ ns = DIV_ROUND_UP_ULL(1000000000ULL, i2c_clk);
+ switch (dev->sm) {
+ case I2C_FREQ_MODE_FAST:
+ case I2C_FREQ_MODE_FAST_PLUS:
+ slsu = DIV_ROUND_UP(100, ns); /* Fast */
+ break;
+ case I2C_FREQ_MODE_HIGH_SPEED:
+ slsu = DIV_ROUND_UP(10, ns); /* High */
+ break;
+ case I2C_FREQ_MODE_STANDARD:
+ default:
+ slsu = DIV_ROUND_UP(250, ns); /* Standard */
+ break;
+ }
+ slsu += 1;
- i2c_clk = clk_get_rate(dev->clk);
+ dev_dbg(&dev->adev->dev, "calculated SLSU = %04x\n", slsu);
+ writel(slsu << 16, dev->virtbase + I2C_SCR);
/*
* The spec says, in case of std. mode the divider is
* 2 whereas it is 3 for fast and fastplus mode of
* operation. TODO - high speed support.
*/
- div = (dev->cfg.clk_freq > 100000) ? 3 : 2;
+ div = (dev->clk_freq > 100000) ? 3 : 2;
/*
* generate the mask for baud rate counters. The controller
@@ -376,7 +409,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
* so set brcr1 to 0.
*/
brcr1 = 0 << 16;
- brcr2 = (i2c_clk/(dev->cfg.clk_freq * div)) & 0xffff;
+ brcr2 = (i2c_clk/(dev->clk_freq * div)) & 0xffff;
/* set the baud rate counter register */
writel((brcr1 | brcr2), dev->virtbase + I2C_BRCR);
@@ -387,7 +420,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
* TODO - support for fast mode plus (up to 1Mb/s)
* and high speed (up to 3.4 Mb/s)
*/
- if (dev->cfg.sm > I2C_FREQ_MODE_FAST) {
+ if (dev->sm > I2C_FREQ_MODE_FAST) {
dev_err(&dev->adev->dev,
"do not support this mode defaulting to std. mode\n");
brcr2 = i2c_clk/(100000 * 2) & 0xffff;
@@ -395,11 +428,11 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
writel(I2C_FREQ_MODE_STANDARD << 4,
dev->virtbase + I2C_CR);
}
- writel(dev->cfg.sm << 4, dev->virtbase + I2C_CR);
+ writel(dev->sm << 4, dev->virtbase + I2C_CR);
/* set the Tx and Rx FIFO threshold */
- writel(dev->cfg.tft, dev->virtbase + I2C_TFTR);
- writel(dev->cfg.rft, dev->virtbase + I2C_RFTR);
+ writel(dev->tft, dev->virtbase + I2C_TFTR);
+ writel(dev->rft, dev->virtbase + I2C_RFTR);
}
/**
@@ -631,28 +664,13 @@ static int nmk_i2c_xfer_one(struct nmk_i2c_dev *dev, u16 flags)
static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg msgs[], int num_msgs)
{
- int status;
+ int status = 0;
int i;
struct nmk_i2c_dev *dev = i2c_get_adapdata(i2c_adap);
int j;
- dev->busy = true;
-
pm_runtime_get_sync(&dev->adev->dev);
- status = clk_prepare_enable(dev->clk);
- if (status) {
- dev_err(&dev->adev->dev, "can't prepare_enable clock\n");
- goto out_clk;
- }
-
- /* Optionaly enable pins to be muxed in and configured */
- pinctrl_pm_select_default_state(&dev->adev->dev);
-
- status = init_hw(dev);
- if (status)
- goto out;
-
/* Attempt three times to send the message queue */
for (j = 0; j < 3; j++) {
/* setup the i2c controller */
@@ -673,16 +691,8 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
break;
}
-out:
- clk_disable_unprepare(dev->clk);
-out_clk:
- /* Optionally let pins go into idle state */
- pinctrl_pm_select_idle_state(&dev->adev->dev);
-
pm_runtime_put_sync(&dev->adev->dev);
- dev->busy = false;
-
/* return the no. messages processed */
if (status)
return status;
@@ -866,43 +876,65 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg)
return IRQ_HANDLED;
}
+#ifdef CONFIG_PM_SLEEP
+static int nmk_i2c_suspend_late(struct device *dev)
+{
+ int ret;
+
+ ret = pm_runtime_force_suspend(dev);
+ if (ret)
+ return ret;
+
+ pinctrl_pm_select_sleep_state(dev);
+ return 0;
+}
+
+static int nmk_i2c_resume_early(struct device *dev)
+{
+ return pm_runtime_force_resume(dev);
+}
+#endif
#ifdef CONFIG_PM
-static int nmk_i2c_suspend(struct device *dev)
+static int nmk_i2c_runtime_suspend(struct device *dev)
{
struct amba_device *adev = to_amba_device(dev);
struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev);
- if (nmk_i2c->busy)
- return -EBUSY;
-
- pinctrl_pm_select_sleep_state(dev);
-
+ clk_disable_unprepare(nmk_i2c->clk);
+ pinctrl_pm_select_idle_state(dev);
return 0;
}
-static int nmk_i2c_resume(struct device *dev)
+static int nmk_i2c_runtime_resume(struct device *dev)
{
- /* First go to the default state */
+ struct amba_device *adev = to_amba_device(dev);
+ struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev);
+ int ret;
+
+ ret = clk_prepare_enable(nmk_i2c->clk);
+ if (ret) {
+ dev_err(dev, "can't prepare_enable clock\n");
+ return ret;
+ }
+
pinctrl_pm_select_default_state(dev);
- /* Then let's idle the pins until the next transfer happens */
- pinctrl_pm_select_idle_state(dev);
- return 0;
+ ret = init_hw(nmk_i2c);
+ if (ret) {
+ clk_disable_unprepare(nmk_i2c->clk);
+ pinctrl_pm_select_idle_state(dev);
+ }
+
+ return ret;
}
-#else
-#define nmk_i2c_suspend NULL
-#define nmk_i2c_resume NULL
#endif
-/*
- * We use noirq so that we suspend late and resume before the wakeup interrupt
- * to ensure that we do the !pm_runtime_suspended() check in resume before
- * there has been a regular pm runtime resume (via pm_runtime_get_sync()).
- */
static const struct dev_pm_ops nmk_i2c_pm = {
- .suspend_noirq = nmk_i2c_suspend,
- .resume_noirq = nmk_i2c_resume,
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(nmk_i2c_suspend_late, nmk_i2c_resume_early)
+ SET_PM_RUNTIME_PM_OPS(nmk_i2c_runtime_suspend,
+ nmk_i2c_runtime_resume,
+ NULL)
};
static unsigned int nmk_i2c_functionality(struct i2c_adapter *adap)
@@ -915,124 +947,98 @@ static const struct i2c_algorithm nmk_i2c_algo = {
.functionality = nmk_i2c_functionality
};
-static struct nmk_i2c_controller u8500_i2c = {
- /*
- * Slave data setup time; 250ns, 100ns, and 10ns, which
- * is 14, 6 and 2 respectively for a 48Mhz i2c clock.
- */
- .slsu = 0xe,
- .tft = 1, /* Tx FIFO threshold */
- .rft = 8, /* Rx FIFO threshold */
- .clk_freq = 400000, /* fast mode operation */
- .timeout = 200, /* Slave response timeout(ms) */
- .sm = I2C_FREQ_MODE_FAST,
-};
-
static void nmk_i2c_of_probe(struct device_node *np,
- struct nmk_i2c_controller *pdata)
+ struct nmk_i2c_dev *nmk)
{
- of_property_read_u32(np, "clock-frequency", &pdata->clk_freq);
+ /* Default to 100 kHz if no frequency is given in the node */
+ if (of_property_read_u32(np, "clock-frequency", &nmk->clk_freq))
+ nmk->clk_freq = 100000;
/* This driver only supports 'standard' and 'fast' modes of operation. */
- if (pdata->clk_freq <= 100000)
- pdata->sm = I2C_FREQ_MODE_STANDARD;
+ if (nmk->clk_freq <= 100000)
+ nmk->sm = I2C_FREQ_MODE_STANDARD;
else
- pdata->sm = I2C_FREQ_MODE_FAST;
+ nmk->sm = I2C_FREQ_MODE_FAST;
+ nmk->tft = 1; /* Tx FIFO threshold */
+ nmk->rft = 8; /* Rx FIFO threshold */
+ nmk->timeout = 200; /* Slave response timeout(ms) */
}
static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
{
int ret = 0;
- struct nmk_i2c_controller *pdata = adev->dev.platform_data;
struct device_node *np = adev->dev.of_node;
struct nmk_i2c_dev *dev;
struct i2c_adapter *adap;
struct i2c_vendor_data *vendor = id->data;
u32 max_fifo_threshold = (vendor->fifodepth / 2) - 1;
- if (!pdata) {
- if (np) {
- pdata = devm_kzalloc(&adev->dev, sizeof(*pdata), GFP_KERNEL);
- if (!pdata) {
- ret = -ENOMEM;
- goto err_no_mem;
- }
- /* Provide the default configuration as a base. */
- memcpy(pdata, &u8500_i2c, sizeof(struct nmk_i2c_controller));
- nmk_i2c_of_probe(np, pdata);
- } else
- /* No i2c configuration found, using the default. */
- pdata = &u8500_i2c;
+ dev = devm_kzalloc(&adev->dev, sizeof(struct nmk_i2c_dev), GFP_KERNEL);
+ if (!dev) {
+ dev_err(&adev->dev, "cannot allocate memory\n");
+ ret = -ENOMEM;
+ goto err_no_mem;
}
+ dev->vendor = vendor;
+ dev->adev = adev;
+ nmk_i2c_of_probe(np, dev);
- if (pdata->tft > max_fifo_threshold) {
+ if (dev->tft > max_fifo_threshold) {
dev_warn(&adev->dev, "requested TX FIFO threshold %u, adjusted down to %u\n",
- pdata->tft, max_fifo_threshold);
- pdata->tft = max_fifo_threshold;
+ dev->tft, max_fifo_threshold);
+ dev->tft = max_fifo_threshold;
}
- if (pdata->rft > max_fifo_threshold) {
+ if (dev->rft > max_fifo_threshold) {
dev_warn(&adev->dev, "requested RX FIFO threshold %u, adjusted down to %u\n",
- pdata->rft, max_fifo_threshold);
- pdata->rft = max_fifo_threshold;
+ dev->rft, max_fifo_threshold);
+ dev->rft = max_fifo_threshold;
}
- dev = kzalloc(sizeof(struct nmk_i2c_dev), GFP_KERNEL);
- if (!dev) {
- dev_err(&adev->dev, "cannot allocate memory\n");
- ret = -ENOMEM;
- goto err_no_mem;
- }
- dev->vendor = vendor;
- dev->busy = false;
- dev->adev = adev;
amba_set_drvdata(adev, dev);
- /* Select default pin state */
- pinctrl_pm_select_default_state(&adev->dev);
- /* If possible, let's go to idle until the first transfer */
- pinctrl_pm_select_idle_state(&adev->dev);
-
- dev->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
+ dev->virtbase = devm_ioremap(&adev->dev, adev->res.start,
+ resource_size(&adev->res));
if (!dev->virtbase) {
ret = -ENOMEM;
- goto err_no_ioremap;
+ goto err_no_mem;
}
dev->irq = adev->irq[0];
- ret = request_irq(dev->irq, i2c_irq_handler, 0,
+ ret = devm_request_irq(&adev->dev, dev->irq, i2c_irq_handler, 0,
DRIVER_NAME, dev);
if (ret) {
dev_err(&adev->dev, "cannot claim the irq %d\n", dev->irq);
- goto err_irq;
+ goto err_no_mem;
}
pm_suspend_ignore_children(&adev->dev, true);
- dev->clk = clk_get(&adev->dev, NULL);
+ dev->clk = devm_clk_get(&adev->dev, NULL);
if (IS_ERR(dev->clk)) {
dev_err(&adev->dev, "could not get i2c clock\n");
ret = PTR_ERR(dev->clk);
- goto err_no_clk;
+ goto err_no_mem;
+ }
+
+ ret = clk_prepare_enable(dev->clk);
+ if (ret) {
+ dev_err(&adev->dev, "can't prepare_enable clock\n");
+ goto err_no_mem;
}
+ init_hw(dev);
+
adap = &dev->adap;
adap->dev.of_node = np;
adap->dev.parent = &adev->dev;
adap->owner = THIS_MODULE;
- adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD | I2C_CLASS_DEPRECATED;
adap->algo = &nmk_i2c_algo;
- adap->timeout = msecs_to_jiffies(pdata->timeout);
+ adap->timeout = msecs_to_jiffies(dev->timeout);
snprintf(adap->name, sizeof(adap->name),
"Nomadik I2C at %pR", &adev->res);
- /* fetch the controller configuration from machine */
- dev->cfg.clk_freq = pdata->clk_freq;
- dev->cfg.slsu = pdata->slsu;
- dev->cfg.tft = pdata->tft;
- dev->cfg.rft = pdata->rft;
- dev->cfg.sm = pdata->sm;
-
i2c_set_adapdata(adap, dev);
dev_info(&adev->dev,
@@ -1042,23 +1048,15 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
ret = i2c_add_adapter(adap);
if (ret) {
dev_err(&adev->dev, "failed to add adapter\n");
- goto err_add_adap;
+ goto err_no_adap;
}
- of_i2c_register_devices(adap);
-
pm_runtime_put(&adev->dev);
return 0;
- err_add_adap:
- clk_put(dev->clk);
- err_no_clk:
- free_irq(dev->irq, dev);
- err_irq:
- iounmap(dev->virtbase);
- err_no_ioremap:
- kfree(dev);
+ err_no_adap:
+ clk_disable_unprepare(dev->clk);
err_no_mem:
return ret;
@@ -1075,13 +1073,9 @@ static int nmk_i2c_remove(struct amba_device *adev)
clear_all_interrupts(dev);
/* disable the controller */
i2c_clr_bit(dev->virtbase + I2C_CR, I2C_CR_PE);
- free_irq(dev->irq, dev);
- iounmap(dev->virtbase);
+ clk_disable_unprepare(dev->clk);
if (res)
release_mem_region(res->start, resource_size(res));
- clk_put(dev->clk);
- pm_runtime_disable(&adev->dev);
- kfree(dev);
return 0;
}
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