Patch mainly from Eric Miao, with minor edits by rmk.
Note: PWM0 and PWM2 share the same register I/O space and clock gating
on pxa{27x, 3xx}, thus PWM2 is treated in the driver as a child PWM of
PWM0. And this is also true for PWM1/3.
Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
tristate
help
Enable support for PXA2xx SSP ports
+
+config PXA_PWM
+ tristate
+ help
+ Enable support for PXA2xx/PXA3xx PWM controllers
endif
# Generic drivers that other drivers may depend upon
obj-$(CONFIG_PXA_SSP) += ssp.o
+obj-$(CONFIG_PXA_PWM) += pwm.o
# SoC-specific code
obj-$(CONFIG_PXA25x) += mfp-pxa2xx.o pxa25x.o
#ifdef CONFIG_PXA25x
+static struct resource pxa25x_resource_pwm0[] = {
+ [0] = {
+ .start = 0x40b00000,
+ .end = 0x40b0000f,
+ .flags = IORESOURCE_MEM,
+ },
+};
+
+struct platform_device pxa25x_device_pwm0 = {
+ .name = "pxa25x-pwm",
+ .id = 0,
+ .resource = pxa25x_resource_pwm0,
+ .num_resources = ARRAY_SIZE(pxa25x_resource_pwm0),
+};
+
+static struct resource pxa25x_resource_pwm1[] = {
+ [0] = {
+ .start = 0x40c00000,
+ .end = 0x40c0000f,
+ .flags = IORESOURCE_MEM,
+ },
+};
+
+struct platform_device pxa25x_device_pwm1 = {
+ .name = "pxa25x-pwm",
+ .id = 1,
+ .resource = pxa25x_resource_pwm1,
+ .num_resources = ARRAY_SIZE(pxa25x_resource_pwm1),
+};
+
static u64 pxa25x_ssp_dma_mask = DMA_BIT_MASK(32);
static struct resource pxa25x_resource_ssp[] = {
.num_resources = ARRAY_SIZE(pxa27x_resource_ssp3),
};
+static struct resource pxa27x_resource_pwm0[] = {
+ [0] = {
+ .start = 0x40b00000,
+ .end = 0x40b0001f,
+ .flags = IORESOURCE_MEM,
+ },
+};
+
+struct platform_device pxa27x_device_pwm0 = {
+ .name = "pxa27x-pwm",
+ .id = 0,
+ .resource = pxa27x_resource_pwm0,
+ .num_resources = ARRAY_SIZE(pxa27x_resource_pwm0),
+};
+
+static struct resource pxa27x_resource_pwm1[] = {
+ [0] = {
+ .start = 0x40c00000,
+ .end = 0x40c0001f,
+ .flags = IORESOURCE_MEM,
+ },
+};
+
+struct platform_device pxa27x_device_pwm1 = {
+ .name = "pxa27x-pwm",
+ .id = 1,
+ .resource = pxa27x_resource_pwm1,
+ .num_resources = ARRAY_SIZE(pxa27x_resource_pwm1),
+};
+
static struct resource pxa27x_resource_camera[] = {
[0] = {
.start = 0x50000000,
extern struct platform_device pxa27x_device_ssp3;
extern struct platform_device pxa3xx_device_ssp4;
+extern struct platform_device pxa25x_device_pwm0;
+extern struct platform_device pxa25x_device_pwm1;
+extern struct platform_device pxa27x_device_pwm0;
+extern struct platform_device pxa27x_device_pwm1;
+
void __init pxa_register_device(struct platform_device *dev, void *data);
--- /dev/null
+/*
+ * linux/arch/arm/mach-pxa/pwm.c
+ *
+ * simple driver for PWM (Pulse Width Modulator) controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 2008-02-13 initial version
+ * eric miao <eric.miao@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+
+#include <asm/div64.h>
+#include <asm/arch/pxa-regs.h>
+
+/* PWM registers and bits definitions */
+#define PWMCR (0x00)
+#define PWMDCR (0x04)
+#define PWMPCR (0x08)
+
+#define PWMCR_SD (1 << 6)
+#define PWMDCR_FD (1 << 10)
+
+struct pwm_device {
+ struct list_head node;
+ struct platform_device *pdev;
+
+ const char *label;
+ struct clk *clk;
+ void __iomem *mmio_base;
+
+ unsigned int use_count;
+ unsigned int pwm_id;
+};
+
+/*
+ * 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)
+{
+ unsigned long long c;
+ unsigned long period_cycles, prescale, pv, dc;
+
+ if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
+ return -EINVAL;
+
+ c = clk_get_rate(pwm->clk);
+ c = c * period_ns;
+ do_div(c, 1000000000);
+ period_cycles = c;
+
+ if (period_cycles < 0)
+ period_cycles = 1;
+ prescale = (period_cycles - 1) / 1024;
+ pv = period_cycles / (prescale + 1) - 1;
+
+ if (prescale > 63)
+ return -EINVAL;
+
+ if (duty_ns == period_ns)
+ dc = PWMDCR_FD;
+ else
+ dc = (pv + 1) * duty_ns / 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);
+
+ return 0;
+}
+EXPORT_SYMBOL(pwm_config);
+
+int pwm_enable(struct pwm_device *pwm)
+{
+ return clk_enable(pwm->clk);
+}
+EXPORT_SYMBOL(pwm_enable);
+
+void pwm_disable(struct pwm_device *pwm)
+{
+ clk_disable(pwm->clk);
+}
+EXPORT_SYMBOL(pwm_disable);
+
+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 && pwm->use_count == 0) {
+ pwm->use_count++;
+ pwm->label = label;
+ found = 1;
+ break;
+ }
+ }
+
+ mutex_unlock(&pwm_lock);
+
+ return (found) ? pwm : NULL;
+}
+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_device *pwm_probe(struct platform_device *pdev,
+ unsigned int pwm_id, struct pwm_device *parent_pwm)
+{
+ struct pwm_device *pwm;
+ struct resource *r;
+ int ret = 0;
+
+ pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
+ if (pwm == NULL) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pwm->clk = clk_get(&pdev->dev, "PWMCLK");
+ if (IS_ERR(pwm->clk)) {
+ ret = PTR_ERR(pwm->clk);
+ goto err_free;
+ }
+
+ pwm->use_count = 0;
+ pwm->pwm_id = pwm_id;
+ pwm->pdev = pdev;
+
+ if (parent_pwm != NULL) {
+ /* registers for the second PWM has offset of 0x10 */
+ pwm->mmio_base = parent_pwm->mmio_base + 0x10;
+ __add_pwm(pwm);
+ return pwm;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (r == NULL) {
+ dev_err(&pdev->dev, "no memory resource defined\n");
+ ret = -ENODEV;
+ goto err_free_clk;
+ }
+
+ r = request_mem_region(r->start, r->end - r->start + 1, pdev->name);
+ if (r == NULL) {
+ dev_err(&pdev->dev, "failed to request memory resource\n");
+ ret = -EBUSY;
+ goto err_free_clk;
+ }
+
+ pwm->mmio_base = ioremap(r->start, r->end - r->start + 1);
+ if (pwm->mmio_base == NULL) {
+ dev_err(&pdev->dev, "failed to ioremap() registers\n");
+ ret = -ENODEV;
+ goto err_free_mem;
+ }
+
+ __add_pwm(pwm);
+ platform_set_drvdata(pdev, pwm);
+ return pwm;
+
+err_free_mem:
+ release_mem_region(r->start, r->end - r->start + 1);
+err_free_clk:
+ clk_put(pwm->clk);
+err_free:
+ kfree(pwm);
+ return ERR_PTR(ret);
+}
+
+static int __devinit pxa25x_pwm_probe(struct platform_device *pdev)
+{
+ struct pwm_device *pwm = pwm_probe(pdev, pdev->id, NULL);
+
+ if (IS_ERR(pwm))
+ return PTR_ERR(pwm);
+
+ return 0;
+}
+
+static int __devinit pxa27x_pwm_probe(struct platform_device *pdev)
+{
+ struct pwm_device *pwm;
+
+ pwm = pwm_probe(pdev, pdev->id * 2, NULL);
+ if (IS_ERR(pwm))
+ return PTR_ERR(pwm);
+
+ pwm = pwm_probe(pdev, pdev->id * 2 + 1, pwm);
+ if (IS_ERR(pwm))
+ return PTR_ERR(pwm);
+
+ return 0;
+}
+
+static int __devexit pwm_remove(struct platform_device *pdev)
+{
+ struct pwm_device *pwm;
+ struct resource *r;
+
+ pwm = platform_get_drvdata(pdev);
+ if (pwm == NULL)
+ return -ENODEV;
+
+ mutex_lock(&pwm_lock);
+ list_del(&pwm->node);
+ mutex_unlock(&pwm_lock);
+
+ iounmap(pwm->mmio_base);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(r->start, r->end - r->start + 1);
+
+ clk_put(pwm->clk);
+ kfree(pwm);
+ return 0;
+}
+
+static struct platform_driver pxa25x_pwm_driver = {
+ .driver = {
+ .name = "pxa25x-pwm",
+ },
+ .probe = pxa25x_pwm_probe,
+ .remove = __devexit_p(pwm_remove),
+};
+
+static struct platform_driver pxa27x_pwm_driver = {
+ .driver = {
+ .name = "pxa27x-pwm",
+ },
+ .probe = pxa27x_pwm_probe,
+ .remove = __devexit_p(pwm_remove),
+};
+
+static int __init pwm_init(void)
+{
+ int ret = 0;
+
+ ret = platform_driver_register(&pxa25x_pwm_driver);
+ if (ret) {
+ printk(KERN_ERR "failed to register pxa25x_pwm_driver\n");
+ return ret;
+ }
+
+ ret = platform_driver_register(&pxa27x_pwm_driver);
+ if (ret) {
+ printk(KERN_ERR "failed to register pxa27x_pwm_driver\n");
+ return ret;
+ }
+
+ return ret;
+}
+arch_initcall(pwm_init);
+
+static void __exit pwm_exit(void)
+{
+ platform_driver_unregister(&pxa25x_pwm_driver);
+ platform_driver_unregister(&pxa27x_pwm_driver);
+}
+module_exit(pwm_exit);
INIT_CKEN("SSPCLK", SSP, 3686400, 0, &pxa25x_device_ssp.dev),
INIT_CKEN("SSPCLK", NSSP, 3686400, 0, &pxa25x_device_nssp.dev),
INIT_CKEN("SSPCLK", ASSP, 3686400, 0, &pxa25x_device_assp.dev),
+ INIT_CKEN("PWMCLK", PWM0, 3686400, 0, &pxa25x_device_pwm0.dev),
+ INIT_CKEN("PWMCLK", PWM1, 3686400, 0, &pxa25x_device_pwm1.dev),
INIT_CKEN("AC97CLK", AC97, 24576000, 0, NULL),
/*
- INIT_CKEN("PWMCLK", PWM0, 3686400, 0, NULL),
- INIT_CKEN("PWMCLK", PWM0, 3686400, 0, NULL),
INIT_CKEN("I2SCLK", I2S, 14745600, 0, NULL),
*/
INIT_CKEN("FICPCLK", FICP, 47923000, 0, NULL),
&pxa25x_device_ssp,
&pxa25x_device_nssp,
&pxa25x_device_assp,
+ &pxa25x_device_pwm0,
+ &pxa25x_device_pwm1,
};
static struct sys_device pxa25x_sysdev[] = {
INIT_CKEN("SSPCLK", SSP1, 13000000, 0, &pxa27x_device_ssp1.dev),
INIT_CKEN("SSPCLK", SSP2, 13000000, 0, &pxa27x_device_ssp2.dev),
INIT_CKEN("SSPCLK", SSP3, 13000000, 0, &pxa27x_device_ssp3.dev),
+ INIT_CKEN("PWMCLK", PWM0, 13000000, 0, &pxa27x_device_pwm0.dev),
+ INIT_CKEN("PWMCLK", PWM1, 13000000, 0, &pxa27x_device_pwm1.dev),
INIT_CKEN("AC97CLK", AC97, 24576000, 0, NULL),
INIT_CKEN("AC97CONFCLK", AC97CONF, 24576000, 0, NULL),
/*
- INIT_CKEN("PWMCLK", PWM0, 13000000, 0, NULL),
INIT_CKEN("MSLCLK", MSL, 48000000, 0, NULL),
INIT_CKEN("USIMCLK", USIM, 48000000, 0, NULL),
INIT_CKEN("MSTKCLK", MEMSTK, 19500000, 0, NULL),
&pxa27x_device_ssp1,
&pxa27x_device_ssp2,
&pxa27x_device_ssp3,
+ &pxa27x_device_pwm0,
+ &pxa27x_device_pwm1,
};
static struct sys_device pxa27x_sysdev[] = {
PXA3xx_CKEN("SSPCLK", SSP2, 13000000, 0, &pxa27x_device_ssp2.dev),
PXA3xx_CKEN("SSPCLK", SSP3, 13000000, 0, &pxa27x_device_ssp3.dev),
PXA3xx_CKEN("SSPCLK", SSP4, 13000000, 0, &pxa3xx_device_ssp4.dev),
+ PXA3xx_CKEN("PWMCLK", PWM0, 13000000, 0, &pxa27x_device_pwm0.dev),
+ PXA3xx_CKEN("PWMCLK", PWM1, 13000000, 0, &pxa27x_device_pwm1.dev),
PXA3xx_CKEN("MMCCLK", MMC1, 19500000, 0, &pxa_device_mci.dev),
PXA3xx_CKEN("MMCCLK", MMC2, 19500000, 0, &pxa3xx_device_mci2.dev),
&pxa27x_device_ssp2,
&pxa27x_device_ssp3,
&pxa3xx_device_ssp4,
+ &pxa27x_device_pwm0,
+ &pxa27x_device_pwm1,
};
static struct sys_device pxa3xx_sysdev[] = {
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