From 29693248edf10830db2ef82b36806e378ff75c67 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Thu, 15 Mar 2012 10:04:35 +0100 Subject: ARM i.MX: Move i.MX pwm driver to pwm framework MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Move the driver to drivers/pwm/ and convert it to use the framework. Signed-off-by: Sascha Hauer [eric@eukrea.com: set chip.dev to prevent probe failure] [eric@eukrea.com: fix pwmchip_add return code test] Signed-off-by: Eric Bénard Signed-off-by: Thierry Reding --- arch/arm/plat-mxc/Kconfig | 6 - arch/arm/plat-mxc/Makefile | 1 - arch/arm/plat-mxc/pwm.c | 306 --------------------------------------------- 3 files changed, 313 deletions(-) delete mode 100644 arch/arm/plat-mxc/pwm.c (limited to 'arch/arm/plat-mxc') diff --git a/arch/arm/plat-mxc/Kconfig b/arch/arm/plat-mxc/Kconfig index c722f9ce6918..baf9064c0844 100644 --- a/arch/arm/plat-mxc/Kconfig +++ b/arch/arm/plat-mxc/Kconfig @@ -47,12 +47,6 @@ config MXC_TZIC config MXC_AVIC bool -config MXC_PWM - tristate "Enable PWM driver" - select HAVE_PWM - help - Enable support for the i.MX PWM controller(s). - config MXC_DEBUG_BOARD bool "Enable MXC debug board(for 3-stack)" help diff --git a/arch/arm/plat-mxc/Makefile b/arch/arm/plat-mxc/Makefile index e81290c27c65..46ba8de2fe4e 100644 --- a/arch/arm/plat-mxc/Makefile +++ b/arch/arm/plat-mxc/Makefile @@ -11,7 +11,6 @@ obj-$(CONFIG_MXC_AVIC) += avic.o obj-$(CONFIG_IMX_HAVE_IOMUX_V1) += iomux-v1.o obj-$(CONFIG_ARCH_MXC_IOMUX_V3) += iomux-v3.o obj-$(CONFIG_IRAM_ALLOC) += iram_alloc.o -obj-$(CONFIG_MXC_PWM) += pwm.o obj-$(CONFIG_MXC_ULPI) += ulpi.o obj-$(CONFIG_MXC_USE_EPIT) += epit.o obj-$(CONFIG_MXC_DEBUG_BOARD) += 3ds_debugboard.o diff --git a/arch/arm/plat-mxc/pwm.c b/arch/arm/plat-mxc/pwm.c deleted file mode 100644 index c0cab2270dd1..000000000000 --- a/arch/arm/plat-mxc/pwm.c +++ /dev/null @@ -1,306 +0,0 @@ -/* - * 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. - * - * Derived from pxa PWM driver by eric miao - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include - - -/* i.MX1 and i.MX21 share the same PWM function block: */ - -#define MX1_PWMC 0x00 /* PWM Control Register */ -#define MX1_PWMS 0x04 /* PWM Sample Register */ -#define MX1_PWMP 0x08 /* PWM Period Register */ - - -/* i.MX27, i.MX31, i.MX35 share the same PWM function block: */ - -#define MX3_PWMCR 0x00 /* PWM Control Register */ -#define MX3_PWMSAR 0x0C /* PWM Sample Register */ -#define MX3_PWMPR 0x10 /* PWM Period Register */ -#define MX3_PWMCR_PRESCALER(x) (((x - 1) & 0xFFF) << 4) -#define MX3_PWMCR_DOZEEN (1 << 24) -#define MX3_PWMCR_WAITEN (1 << 23) -#define MX3_PWMCR_DBGEN (1 << 22) -#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16) -#define MX3_PWMCR_CLKSRC_IPG (1 << 16) -#define MX3_PWMCR_EN (1 << 0) - - - -struct pwm_device { - struct list_head node; - 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; -}; - -int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) -{ - if (pwm == NULL || period_ns == 0 || duty_ns > period_ns) - return -EINVAL; - - if (!(cpu_is_mx1() || cpu_is_mx21())) { - unsigned long long c; - unsigned long period_cycles, duty_cycles, prescale; - u32 cr; - - c = clk_get_rate(pwm->clk); - c = c * period_ns; - do_div(c, 1000000000); - period_cycles = c; - - prescale = period_cycles / 0x10000 + 1; - - period_cycles /= prescale; - c = (unsigned long long)period_cycles * duty_ns; - do_div(c, period_ns); - duty_cycles = c; - - /* - * according to imx pwm RM, the real period value should be - * PERIOD value in PWMPR plus 2. - */ - if (period_cycles > 2) - period_cycles -= 2; - else - period_cycles = 0; - - writel(duty_cycles, pwm->mmio_base + MX3_PWMSAR); - writel(period_cycles, pwm->mmio_base + MX3_PWMPR); - - cr = MX3_PWMCR_PRESCALER(prescale) | - MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN | - MX3_PWMCR_DBGEN | MX3_PWMCR_EN; - - if (cpu_is_mx25()) - cr |= MX3_PWMCR_CLKSRC_IPG; - else - cr |= MX3_PWMCR_CLKSRC_IPG_HIGH; - - writel(cr, pwm->mmio_base + MX3_PWMCR); - } else if (cpu_is_mx1() || cpu_is_mx21()) { - /* The PWM subsystem allows for exact frequencies. However, - * I cannot connect a scope on my device to the PWM line and - * thus cannot provide the program the PWM controller - * exactly. Instead, I'm relying on the fact that the - * Bootloader (u-boot or WinCE+haret) has programmed the PWM - * function group already. So I'll just modify the PWM sample - * register to follow the ratio of duty_ns vs. period_ns - * accordingly. - * - * This is good enough for programming the brightness of - * the LCD backlight. - * - * The real implementation would divide PERCLK[0] first by - * both the prescaler (/1 .. /128) and then by CLKSEL - * (/2 .. /16). - */ - u32 max = readl(pwm->mmio_base + MX1_PWMP); - u32 p = max * duty_ns / period_ns; - writel(max - p, pwm->mmio_base + MX1_PWMS); - } else { - BUG(); - } - - return 0; -} -EXPORT_SYMBOL(pwm_config); - -int pwm_enable(struct pwm_device *pwm) -{ - int rc = 0; - - if (!pwm->clk_enabled) { - rc = clk_prepare_enable(pwm->clk); - if (!rc) - pwm->clk_enabled = 1; - } - return rc; -} -EXPORT_SYMBOL(pwm_enable); - -void pwm_disable(struct pwm_device *pwm) -{ - writel(0, pwm->mmio_base + MX3_PWMCR); - - if (pwm->clk_enabled) { - clk_disable_unprepare(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 int __devinit mxc_pwm_probe(struct platform_device *pdev) -{ - 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 -ENOMEM; - } - - pwm->clk = clk_get(&pdev->dev, "pwm"); - - if (IS_ERR(pwm->clk)) { - ret = PTR_ERR(pwm->clk); - goto err_free; - } - - pwm->clk_enabled = 0; - - pwm->use_count = 0; - pwm->pwm_id = 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; - } - - mutex_lock(&pwm_lock); - list_add_tail(&pwm->node, &pwm_list); - mutex_unlock(&pwm_lock); - - 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 mxc_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, resource_size(r)); - - clk_put(pwm->clk); - - kfree(pwm); - return 0; -} - -static struct platform_driver mxc_pwm_driver = { - .driver = { - .name = "mxc_pwm", - }, - .probe = mxc_pwm_probe, - .remove = __devexit_p(mxc_pwm_remove), -}; - -static int __init mxc_pwm_init(void) -{ - return platform_driver_register(&mxc_pwm_driver); -} -arch_initcall(mxc_pwm_init); - -static void __exit mxc_pwm_exit(void) -{ - platform_driver_unregister(&mxc_pwm_driver); -} -module_exit(mxc_pwm_exit); - -MODULE_LICENSE("GPL v2"); -MODULE_AUTHOR("Sascha Hauer "); -- cgit v1.2.3-59-g8ed1b