From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: [PATCH v2 09/10] pwm: Add PXA support Date: Mon, 6 Feb 2012 16:19:44 +0100 Message-ID: <1328541585-24642-10-git-send-email-thierry.reding@avionic-design.de> References: <1328541585-24642-1-git-send-email-thierry.reding@avionic-design.de> Return-path: In-Reply-To: <1328541585-24642-1-git-send-email-thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Sascha Hauer , Arnd Bergmann , Matthias Kaehlcke , Kurt Van Dijck , Rob Herring , Grant Likely , Colin Cross , Olof Johansson , Richard Purdie , Mark Brown , Mitch Bradley , Mike Frysinger , Eric Miao List-Id: linux-tegra@vger.kernel.org Signed-off-by: Thierry Reding --- arch/arm/plat-pxa/Makefile | 1 - arch/arm/plat-pxa/pwm.c | 304 -------------------------------------------- drivers/pwm/Kconfig | 9 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-pxa.c | 243 +++++++++++++++++++++++++++++++++++ 5 files changed, 253 insertions(+), 305 deletions(-) delete mode 100644 arch/arm/plat-pxa/pwm.c create mode 100644 drivers/pwm/pwm-pxa.c 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/arch/arm/plat-pxa/pwm.c b/arch/arm/plat-pxa/pwm.c deleted file mode 100644 index ef32686..0000000 --- a/arch/arm/plat-pxa/pwm.c +++ /dev/null @@ -1,304 +0,0 @@ -/* - * 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 - */ - -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -#define HAS_SECONDARY_PWM 0x10 -#define PWM_ID_BASE(d) ((d) & 0xf) - -static const struct platform_device_id pwm_id_table[] = { - /* PWM has_secondary_pwm? */ - { "pxa25x-pwm", 0 }, - { "pxa27x-pwm", 0 | HAS_SECONDARY_PWM }, - { "pxa168-pwm", 1 }, - { "pxa910-pwm", 1 }, - { }, -}; -MODULE_DEVICE_TABLE(platform, pwm_id_table); - -/* 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 pwm_device *secondary; - struct platform_device *pdev; - - const char *label; - struct clk *clk; - int clk_enabled; - 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 < 1) - 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) -{ - int rc = 0; - - if (!pwm->clk_enabled) { - rc = clk_enable(pwm->clk); - if (!rc) - pwm->clk_enabled = 1; - } - return rc; -} -EXPORT_SYMBOL(pwm_enable); - -void pwm_disable(struct pwm_device *pwm) -{ - if (pwm->clk_enabled) { - clk_disable(pwm->clk); - pwm->clk_enabled = 0; - } -} -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) { - found = 1; - break; - } - } - - 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 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 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 -ENOMEM; - } - - pwm->clk = clk_get(&pdev->dev, NULL); - if (IS_ERR(pwm->clk)) { - ret = PTR_ERR(pwm->clk); - goto err_free; - } - pwm->clk_enabled = 0; - - pwm->use_count = 0; - pwm->pwm_id = PWM_ID_BASE(id->driver_data) + pdev->id; - pwm->pdev = pdev; - - 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, resource_size(r), 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, resource_size(r)); - if (pwm->mmio_base == NULL) { - dev_err(&pdev->dev, "failed to ioremap() registers\n"); - ret = -ENODEV; - 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; - } - - __add_pwm(pwm); - if (secondary) - __add_pwm(secondary); - - platform_set_drvdata(pdev, pwm); - return 0; - -err_free_mem: - release_mem_region(r->start, resource_size(r)); -err_free_clk: - clk_put(pwm->clk); -err_free: - kfree(pwm); - return ret; -} - -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); - - if (pwm->secondary) { - list_del(&pwm->secondary->node); - kfree(pwm->secondary); - } - - 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, resource_size(r)); - - clk_put(pwm->clk); - kfree(pwm); - return 0; -} - -static struct platform_driver pwm_driver = { - .driver = { - .name = "pxa25x-pwm", - .owner = THIS_MODULE, - }, - .probe = pwm_probe, - .remove = __devexit_p(pwm_remove), - .id_table = pwm_id_table, -}; - -static int __init pwm_init(void) -{ - return platform_driver_register(&pwm_driver); -} -arch_initcall(pwm_init); - -static void __exit pwm_exit(void) -{ - platform_driver_unregister(&pwm_driver); -} -module_exit(pwm_exit); - -MODULE_LICENSE("GPL v2"); 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/drivers/pwm/pwm-pxa.c b/drivers/pwm/pwm-pxa.c new file mode 100644 index 0000000..6434b18 --- /dev/null +++ b/drivers/pwm/pwm-pxa.c @@ -0,0 +1,243 @@ +/* + * 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 + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define HAS_SECONDARY_PWM 0x10 +#define PWM_ID_BASE(d) ((d) & 0xf) + +static const struct platform_device_id pwm_id_table[] = { + /* PWM has_secondary_pwm? */ + { "pxa25x-pwm", 0 }, + { "pxa27x-pwm", 0 | HAS_SECONDARY_PWM }, + { "pxa168-pwm", 1 }, + { "pxa910-pwm", 1 }, + { }, +}; +MODULE_DEVICE_TABLE(platform, pwm_id_table); + +/* 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 pxa_pwm_chip { + struct pwm_chip chip; + struct device *dev; + + struct clk *clk; + int clk_enabled; + void __iomem *mmio_base; +}; + +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 + */ +static int pxa_pwm_config(struct pwm_chip *chip, unsigned int 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; + + if (period_ns == 0 || duty_ns > period_ns) + return -EINVAL; + + offset = (pwm - chip->base) ? 0x10 : 0; + + c = clk_get_rate(pc->clk); + c = c * period_ns; + do_div(c, 1000000000); + period_cycles = c; + + if (period_cycles < 1) + 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(pc->clk); + __raw_writel(prescale, pc->mmio_base + offset + PWMCR); + __raw_writel(dc, pc->mmio_base + offset + PWMDCR); + __raw_writel(pv, pc->mmio_base + offset + PWMPCR); + clk_disable(pc->clk); + + return 0; +} + +static int pxa_pwm_enable(struct pwm_chip *chip, unsigned int pwm) +{ + struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); + int rc = 0; + + if (!pc->clk_enabled) { + rc = clk_enable(pc->clk); + if (!rc) + pc->clk_enabled = 1; + } + return rc; +} + +static void pxa_pwm_disable(struct pwm_chip *chip, unsigned int pwm) +{ + struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); + + if (pc->clk_enabled) { + clk_disable(pc->clk); + pc->clk_enabled = 0; + } +} + +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 pxa_pwm_chip *pwm; + struct resource *r; + int ret = 0; + + pwm = kzalloc(sizeof(*pwm), GFP_KERNEL); + if (pwm == NULL) { + dev_err(&pdev->dev, "failed to allocate memory\n"); + return -ENOMEM; + } + + pwm->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm->clk)) { + ret = PTR_ERR(pwm->clk); + goto err_free; + } + pwm->clk_enabled = 0; + + 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) { + dev_err(&pdev->dev, "no memory resource defined\n"); + ret = -ENODEV; + goto err_free_clk; + } + + r = request_mem_region(r->start, resource_size(r), 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, resource_size(r)); + if (pwm->mmio_base == NULL) { + dev_err(&pdev->dev, "failed to ioremap() registers\n"); + ret = -ENODEV; + goto err_free_mem; + } + + ret = pwmchip_add(&pwm->chip); + if (ret < 0) { + dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, pwm); + return 0; + +err_free_mem: + release_mem_region(r->start, resource_size(r)); +err_free_clk: + clk_put(pwm->clk); +err_free: + kfree(pwm); + return ret; +} + +static int __devexit pwm_remove(struct platform_device *pdev) +{ + struct pxa_pwm_chip *chip; + struct resource *r; + + chip = platform_get_drvdata(pdev); + if (chip == NULL) + return -ENODEV; + + pwmchip_remove(&chip->chip); + + iounmap(chip->mmio_base); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(r->start, resource_size(r)); + + clk_put(chip->clk); + kfree(chip); + return 0; +} + +static struct platform_driver pwm_driver = { + .driver = { + .name = "pxa25x-pwm", + .owner = THIS_MODULE, + }, + .probe = pwm_probe, + .remove = __devexit_p(pwm_remove), + .id_table = pwm_id_table, +}; + +static int __init pwm_init(void) +{ + return platform_driver_register(&pwm_driver); +} +arch_initcall(pwm_init); + +static void __exit pwm_exit(void) +{ + platform_driver_unregister(&pwm_driver); +} +module_exit(pwm_exit); + +MODULE_LICENSE("GPL v2"); -- 1.7.9 From mboxrd@z Thu Jan 1 00:00:00 1970 From: thierry.reding@avionic-design.de (Thierry Reding) Date: Mon, 6 Feb 2012 16:19:44 +0100 Subject: [PATCH v2 09/10] pwm: Add PXA support In-Reply-To: <1328541585-24642-1-git-send-email-thierry.reding@avionic-design.de> References: <1328541585-24642-1-git-send-email-thierry.reding@avionic-design.de> Message-ID: <1328541585-24642-10-git-send-email-thierry.reding@avionic-design.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Signed-off-by: Thierry Reding --- arch/arm/plat-pxa/Makefile | 1 - arch/arm/plat-pxa/pwm.c | 304 -------------------------------------------- drivers/pwm/Kconfig | 9 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-pxa.c | 243 +++++++++++++++++++++++++++++++++++ 5 files changed, 253 insertions(+), 305 deletions(-) delete mode 100644 arch/arm/plat-pxa/pwm.c create mode 100644 drivers/pwm/pwm-pxa.c 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/arch/arm/plat-pxa/pwm.c b/arch/arm/plat-pxa/pwm.c deleted file mode 100644 index ef32686..0000000 --- a/arch/arm/plat-pxa/pwm.c +++ /dev/null @@ -1,304 +0,0 @@ -/* - * 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 - */ - -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -#define HAS_SECONDARY_PWM 0x10 -#define PWM_ID_BASE(d) ((d) & 0xf) - -static const struct platform_device_id pwm_id_table[] = { - /* PWM has_secondary_pwm? */ - { "pxa25x-pwm", 0 }, - { "pxa27x-pwm", 0 | HAS_SECONDARY_PWM }, - { "pxa168-pwm", 1 }, - { "pxa910-pwm", 1 }, - { }, -}; -MODULE_DEVICE_TABLE(platform, pwm_id_table); - -/* 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 pwm_device *secondary; - struct platform_device *pdev; - - const char *label; - struct clk *clk; - int clk_enabled; - 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 < 1) - 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) -{ - int rc = 0; - - if (!pwm->clk_enabled) { - rc = clk_enable(pwm->clk); - if (!rc) - pwm->clk_enabled = 1; - } - return rc; -} -EXPORT_SYMBOL(pwm_enable); - -void pwm_disable(struct pwm_device *pwm) -{ - if (pwm->clk_enabled) { - clk_disable(pwm->clk); - pwm->clk_enabled = 0; - } -} -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) { - found = 1; - break; - } - } - - 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 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 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 -ENOMEM; - } - - pwm->clk = clk_get(&pdev->dev, NULL); - if (IS_ERR(pwm->clk)) { - ret = PTR_ERR(pwm->clk); - goto err_free; - } - pwm->clk_enabled = 0; - - pwm->use_count = 0; - pwm->pwm_id = PWM_ID_BASE(id->driver_data) + pdev->id; - pwm->pdev = pdev; - - 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, resource_size(r), 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, resource_size(r)); - if (pwm->mmio_base == NULL) { - dev_err(&pdev->dev, "failed to ioremap() registers\n"); - ret = -ENODEV; - 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; - } - - __add_pwm(pwm); - if (secondary) - __add_pwm(secondary); - - platform_set_drvdata(pdev, pwm); - return 0; - -err_free_mem: - release_mem_region(r->start, resource_size(r)); -err_free_clk: - clk_put(pwm->clk); -err_free: - kfree(pwm); - return ret; -} - -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); - - if (pwm->secondary) { - list_del(&pwm->secondary->node); - kfree(pwm->secondary); - } - - 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, resource_size(r)); - - clk_put(pwm->clk); - kfree(pwm); - return 0; -} - -static struct platform_driver pwm_driver = { - .driver = { - .name = "pxa25x-pwm", - .owner = THIS_MODULE, - }, - .probe = pwm_probe, - .remove = __devexit_p(pwm_remove), - .id_table = pwm_id_table, -}; - -static int __init pwm_init(void) -{ - return platform_driver_register(&pwm_driver); -} -arch_initcall(pwm_init); - -static void __exit pwm_exit(void) -{ - platform_driver_unregister(&pwm_driver); -} -module_exit(pwm_exit); - -MODULE_LICENSE("GPL v2"); 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/drivers/pwm/pwm-pxa.c b/drivers/pwm/pwm-pxa.c new file mode 100644 index 0000000..6434b18 --- /dev/null +++ b/drivers/pwm/pwm-pxa.c @@ -0,0 +1,243 @@ +/* + * 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 + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define HAS_SECONDARY_PWM 0x10 +#define PWM_ID_BASE(d) ((d) & 0xf) + +static const struct platform_device_id pwm_id_table[] = { + /* PWM has_secondary_pwm? */ + { "pxa25x-pwm", 0 }, + { "pxa27x-pwm", 0 | HAS_SECONDARY_PWM }, + { "pxa168-pwm", 1 }, + { "pxa910-pwm", 1 }, + { }, +}; +MODULE_DEVICE_TABLE(platform, pwm_id_table); + +/* 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 pxa_pwm_chip { + struct pwm_chip chip; + struct device *dev; + + struct clk *clk; + int clk_enabled; + void __iomem *mmio_base; +}; + +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 + */ +static int pxa_pwm_config(struct pwm_chip *chip, unsigned int 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; + + if (period_ns == 0 || duty_ns > period_ns) + return -EINVAL; + + offset = (pwm - chip->base) ? 0x10 : 0; + + c = clk_get_rate(pc->clk); + c = c * period_ns; + do_div(c, 1000000000); + period_cycles = c; + + if (period_cycles < 1) + 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(pc->clk); + __raw_writel(prescale, pc->mmio_base + offset + PWMCR); + __raw_writel(dc, pc->mmio_base + offset + PWMDCR); + __raw_writel(pv, pc->mmio_base + offset + PWMPCR); + clk_disable(pc->clk); + + return 0; +} + +static int pxa_pwm_enable(struct pwm_chip *chip, unsigned int pwm) +{ + struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); + int rc = 0; + + if (!pc->clk_enabled) { + rc = clk_enable(pc->clk); + if (!rc) + pc->clk_enabled = 1; + } + return rc; +} + +static void pxa_pwm_disable(struct pwm_chip *chip, unsigned int pwm) +{ + struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip); + + if (pc->clk_enabled) { + clk_disable(pc->clk); + pc->clk_enabled = 0; + } +} + +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 pxa_pwm_chip *pwm; + struct resource *r; + int ret = 0; + + pwm = kzalloc(sizeof(*pwm), GFP_KERNEL); + if (pwm == NULL) { + dev_err(&pdev->dev, "failed to allocate memory\n"); + return -ENOMEM; + } + + pwm->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm->clk)) { + ret = PTR_ERR(pwm->clk); + goto err_free; + } + pwm->clk_enabled = 0; + + 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) { + dev_err(&pdev->dev, "no memory resource defined\n"); + ret = -ENODEV; + goto err_free_clk; + } + + r = request_mem_region(r->start, resource_size(r), 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, resource_size(r)); + if (pwm->mmio_base == NULL) { + dev_err(&pdev->dev, "failed to ioremap() registers\n"); + ret = -ENODEV; + goto err_free_mem; + } + + ret = pwmchip_add(&pwm->chip); + if (ret < 0) { + dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, pwm); + return 0; + +err_free_mem: + release_mem_region(r->start, resource_size(r)); +err_free_clk: + clk_put(pwm->clk); +err_free: + kfree(pwm); + return ret; +} + +static int __devexit pwm_remove(struct platform_device *pdev) +{ + struct pxa_pwm_chip *chip; + struct resource *r; + + chip = platform_get_drvdata(pdev); + if (chip == NULL) + return -ENODEV; + + pwmchip_remove(&chip->chip); + + iounmap(chip->mmio_base); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(r->start, resource_size(r)); + + clk_put(chip->clk); + kfree(chip); + return 0; +} + +static struct platform_driver pwm_driver = { + .driver = { + .name = "pxa25x-pwm", + .owner = THIS_MODULE, + }, + .probe = pwm_probe, + .remove = __devexit_p(pwm_remove), + .id_table = pwm_id_table, +}; + +static int __init pwm_init(void) +{ + return platform_driver_register(&pwm_driver); +} +arch_initcall(pwm_init); + +static void __exit pwm_exit(void) +{ + platform_driver_unregister(&pwm_driver); +} +module_exit(pwm_exit); + +MODULE_LICENSE("GPL v2"); -- 1.7.9