diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-30 09:22:37 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-30 09:22:37 -0700 |
commit | 9ec97169e7d6afe2f8206d694d1411fb3bb49853 (patch) | |
tree | 9d24c8cd440a312f96b70db5cdaaef1136787003 /arch/arm/plat-mxc | |
parent | a410963ba4c0c768302f0298e258b1ee940e8316 (diff) | |
parent | 19891b20e7c275feb92d669f4b1879861f7e8c25 (diff) |
Merge branch 'for-3.6' of git://gitorious.org/linux-pwm/linux-pwm
Pull PWM subsystem from Thierry Reding:
"The new PWM subsystem aims at collecting all implementations of the
legacy PWM API and to eventually replace it completely.
The subsystem has been in development for over half a year now and
many drivers have already been converted. It has been in linux-next
for a couple of weeks and there have been no major issues so I think
it is ready for inclusion in your tree."
Arnd Bergmann <arnd@arndb.de>:
"Very much Ack on the new subsystem. It uses the interface
declarations as the previously separate pwm drivers, so nothing
changes for now in the drivers using it, although it enables us to
change those more easily in the future if we want to.
This work is also one of the missing pieces that are required to
eventually build ARM kernels for multiple platforms, which is
currently prohibited (amongs other things) by the fact that you cannot
have more than one driver exporting the pwm functions."
Tested-and-acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Philip, Avinash <avinashphilip@ti.com> # TI's AM33xx platforms
Acked-By: Alexandre Pereira da Silva <aletes.xgr@gmail.com> # LPC32XX
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sachin Kamat <sachin.kamat@linaro.org>
Fix up trivial conflicts with other cleanups and DT updates.
* 'for-3.6' of git://gitorious.org/linux-pwm/linux-pwm: (36 commits)
pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
pwm: pwm-tiecap: PWM driver support for ECAP APWM
pwm: fix used-uninitialized warning in pwm_get()
pwm: add lpc32xx PWM support
pwm_backlight: pass correct brightness to callback
pwm: Use pr_* functions in pwm-samsung.c file
pwm: Convert pwm-samsung to use devm_* APIs
pwm: Convert pwm-tegra to use devm_clk_get()
pwm: pwm-mxs: Return proper error if pwmchip_remove() fails
pwm: pwm-bfin: Return proper error if pwmchip_remove() fails
pwm: pxa: Propagate pwmchip_remove() error
pwm: Convert pwm-pxa to use devm_* APIs
pwm: Convert pwm-vt8500 to use devm_* APIs
pwm: Convert pwm-imx to use devm_* APIs
pwm: Conflict with legacy PWM API
pwm: pwm-mxs: add pinctrl support
pwm: pwm-mxs: use devm_* managed functions
pwm: pwm-mxs: use global reset function stmp_reset_block
pwm: pwm-mxs: encode soc name in compatible string
pwm: Take over maintainership of the PWM subsystem
...
Diffstat (limited to 'arch/arm/plat-mxc')
-rw-r--r-- | arch/arm/plat-mxc/Kconfig | 6 | ||||
-rw-r--r-- | arch/arm/plat-mxc/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/plat-mxc/pwm.c | 306 |
3 files changed, 0 insertions, 313 deletions
diff --git a/arch/arm/plat-mxc/Kconfig b/arch/arm/plat-mxc/Kconfig index c722f9ce691..baf9064c084 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 63b064b5c1d..6ac72003115 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 c0cab2270dd..00000000000 --- 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 <eric.miao@marvell.com> - */ - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/platform_device.h> -#include <linux/slab.h> -#include <linux/err.h> -#include <linux/clk.h> -#include <linux/io.h> -#include <linux/pwm.h> -#include <mach/hardware.h> - - -/* 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 <s.hauer@pengutronix.de>"); |