[PATCH v6 11/17] pwm: Move PXA PWM driver to PWM framework
Thierry Reding
thierry.reding at avionic-design.de
Tue Apr 10 11:06:34 EDT 2012
This commit moves the PXA PWM driver to the drivers/pwm subdirectory and
converts it to use the new PWM framework.
Signed-off-by: Thierry Reding <thierry.reding at avionic-design.de>
---
Changes in v5:
- replace __raw_readl()/__raw_writel() by readl()/writel()
- use clk_prepare_enable() and clk_disable_unprepare()
Changes in v3:
- update PWM ops for changes in patch 2
arch/arm/plat-pxa/Makefile | 1 -
drivers/pwm/Kconfig | 9 ++
drivers/pwm/Makefile | 1 +
arch/arm/plat-pxa/pwm.c => drivers/pwm/pwm-pxa.c | 172 ++++++++--------------
4 files changed, 68 insertions(+), 115 deletions(-)
rename arch/arm/plat-pxa/pwm.c => drivers/pwm/pwm-pxa.c (57%)
diff --git a/arch/arm/plat-pxa/Makefile b/arch/arm/plat-pxa/Makefile
index f302d04..af8e484 100644
--- a/arch/arm/plat-pxa/Makefile
+++ b/arch/arm/plat-pxa/Makefile
@@ -8,5 +8,4 @@ obj-$(CONFIG_PXA3xx) += mfp.o
obj-$(CONFIG_PXA95x) += mfp.o
obj-$(CONFIG_ARCH_MMP) += mfp.o
-obj-$(CONFIG_HAVE_PWM) += pwm.o
obj-$(CONFIG_PXA_SSP) += ssp.o
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index eb54042..0ef4f30 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -18,6 +18,15 @@ config PWM_BFIN
To compile this driver as a module, choose M here: the module
will be called pwm-bfin.
+config PWM_PXA
+ tristate "PXA PWM support"
+ depends on ARCH_PXA
+ help
+ Generic PWM framework driver for PXA.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-pxa.
+
config PWM_TEGRA
tristate "NVIDIA Tegra PWM support"
depends on ARCH_TEGRA
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 251b8d2..e859c51 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_PWM) += core.o
obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
+obj-$(CONFIG_PWM_PXA) += pwm-pxa.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
diff --git a/arch/arm/plat-pxa/pwm.c b/drivers/pwm/pwm-pxa.c
similarity index 57%
rename from arch/arm/plat-pxa/pwm.c
rename to drivers/pwm/pwm-pxa.c
index ef32686..d5c6ce5 100644
--- a/arch/arm/plat-pxa/pwm.c
+++ b/drivers/pwm/pwm-pxa.c
@@ -43,33 +43,39 @@ MODULE_DEVICE_TABLE(platform, pwm_id_table);
#define PWMCR_SD (1 << 6)
#define PWMDCR_FD (1 << 10)
-struct pwm_device {
- struct list_head node;
- struct pwm_device *secondary;
- struct platform_device *pdev;
+struct pxa_pwm_chip {
+ struct pwm_chip chip;
+ struct device *dev;
- const char *label;
struct clk *clk;
int clk_enabled;
void __iomem *mmio_base;
-
- unsigned int use_count;
- unsigned int pwm_id;
};
+static inline struct pxa_pwm_chip *to_pxa_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct pxa_pwm_chip, chip);
+}
+
/*
* period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE
* duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
*/
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+static int pxa_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
{
+ struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
unsigned long long c;
unsigned long period_cycles, prescale, pv, dc;
+ unsigned long offset;
+ int rc;
- if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
+ if (period_ns == 0 || duty_ns > period_ns)
return -EINVAL;
- c = clk_get_rate(pwm->clk);
+ offset = pwm->hwpwm ? 0x10 : 0;
+
+ c = clk_get_rate(pc->clk);
c = c * period_ns;
do_div(c, 1000000000);
period_cycles = c;
@@ -90,98 +96,56 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
/* NOTE: the clock to PWM has to be enabled first
* before writing to the registers
*/
- clk_enable(pwm->clk);
- __raw_writel(prescale, pwm->mmio_base + PWMCR);
- __raw_writel(dc, pwm->mmio_base + PWMDCR);
- __raw_writel(pv, pwm->mmio_base + PWMPCR);
- clk_disable(pwm->clk);
+ rc = clk_prepare_enable(pc->clk);
+ if (rc < 0)
+ return rc;
+
+ writel(prescale, pc->mmio_base + offset + PWMCR);
+ writel(dc, pc->mmio_base + offset + PWMDCR);
+ writel(pv, pc->mmio_base + offset + PWMPCR);
+ clk_disable_unprepare(pc->clk);
return 0;
}
-EXPORT_SYMBOL(pwm_config);
-int pwm_enable(struct pwm_device *pwm)
+static int pxa_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
+ struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
int rc = 0;
- if (!pwm->clk_enabled) {
- rc = clk_enable(pwm->clk);
+ if (!pc->clk_enabled) {
+ rc = clk_prepare_enable(pc->clk);
if (!rc)
- pwm->clk_enabled = 1;
+ pc->clk_enabled++;
}
return rc;
}
-EXPORT_SYMBOL(pwm_enable);
-void pwm_disable(struct pwm_device *pwm)
+static void pxa_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
- if (pwm->clk_enabled) {
- clk_disable(pwm->clk);
- pwm->clk_enabled = 0;
- }
-}
-EXPORT_SYMBOL(pwm_disable);
+ struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);
-static DEFINE_MUTEX(pwm_lock);
-static LIST_HEAD(pwm_list);
-
-struct pwm_device *pwm_request(int pwm_id, const char *label)
-{
- struct pwm_device *pwm;
- int found = 0;
-
- mutex_lock(&pwm_lock);
-
- list_for_each_entry(pwm, &pwm_list, node) {
- if (pwm->pwm_id == pwm_id) {
- found = 1;
- break;
- }
+ if (pc->clk_enabled) {
+ clk_disable_unprepare(pc->clk);
+ pc->clk_enabled--;
}
-
- if (found) {
- if (pwm->use_count == 0) {
- pwm->use_count++;
- pwm->label = label;
- } else
- pwm = ERR_PTR(-EBUSY);
- } else
- pwm = ERR_PTR(-ENOENT);
-
- mutex_unlock(&pwm_lock);
- return pwm;
}
-EXPORT_SYMBOL(pwm_request);
-
-void pwm_free(struct pwm_device *pwm)
-{
- mutex_lock(&pwm_lock);
- if (pwm->use_count) {
- pwm->use_count--;
- pwm->label = NULL;
- } else
- pr_warning("PWM device already freed\n");
-
- mutex_unlock(&pwm_lock);
-}
-EXPORT_SYMBOL(pwm_free);
-
-static inline void __add_pwm(struct pwm_device *pwm)
-{
- mutex_lock(&pwm_lock);
- list_add_tail(&pwm->node, &pwm_list);
- mutex_unlock(&pwm_lock);
-}
+static struct pwm_ops pxa_pwm_ops = {
+ .config = pxa_pwm_config,
+ .enable = pxa_pwm_enable,
+ .disable = pxa_pwm_disable,
+ .owner = THIS_MODULE,
+};
static int __devinit pwm_probe(struct platform_device *pdev)
{
const struct platform_device_id *id = platform_get_device_id(pdev);
- struct pwm_device *pwm, *secondary = NULL;
+ struct pxa_pwm_chip *pwm;
struct resource *r;
int ret = 0;
- pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
+ pwm = kzalloc(sizeof(*pwm), GFP_KERNEL);
if (pwm == NULL) {
dev_err(&pdev->dev, "failed to allocate memory\n");
return -ENOMEM;
@@ -194,9 +158,10 @@ static int __devinit pwm_probe(struct platform_device *pdev)
}
pwm->clk_enabled = 0;
- pwm->use_count = 0;
- pwm->pwm_id = PWM_ID_BASE(id->driver_data) + pdev->id;
- pwm->pdev = pdev;
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.ops = &pxa_pwm_ops;
+ pwm->chip.base = -1;
+ pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (r == NULL) {
@@ -219,25 +184,12 @@ static int __devinit pwm_probe(struct platform_device *pdev)
goto err_free_mem;
}
- if (id->driver_data & HAS_SECONDARY_PWM) {
- secondary = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
- if (secondary == NULL) {
- ret = -ENOMEM;
- goto err_free_mem;
- }
-
- *secondary = *pwm;
- pwm->secondary = secondary;
-
- /* registers for the second PWM has offset of 0x10 */
- secondary->mmio_base = pwm->mmio_base + 0x10;
- secondary->pwm_id = pdev->id + 2;
+ ret = pwmchip_add(&pwm->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+ return ret;
}
- __add_pwm(pwm);
- if (secondary)
- __add_pwm(secondary);
-
platform_set_drvdata(pdev, pwm);
return 0;
@@ -252,30 +204,22 @@ err_free:
static int __devexit pwm_remove(struct platform_device *pdev)
{
- struct pwm_device *pwm;
+ struct pxa_pwm_chip *chip;
struct resource *r;
- pwm = platform_get_drvdata(pdev);
- if (pwm == NULL)
+ chip = platform_get_drvdata(pdev);
+ if (chip == NULL)
return -ENODEV;
- mutex_lock(&pwm_lock);
-
- if (pwm->secondary) {
- list_del(&pwm->secondary->node);
- kfree(pwm->secondary);
- }
+ pwmchip_remove(&chip->chip);
- list_del(&pwm->node);
- mutex_unlock(&pwm_lock);
-
- iounmap(pwm->mmio_base);
+ iounmap(chip->mmio_base);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(r->start, resource_size(r));
- clk_put(pwm->clk);
- kfree(pwm);
+ clk_put(chip->clk);
+ kfree(chip);
return 0;
}
--
1.7.9.6
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