diff options
author | Hartley Sweeten <hartleys@visionengravers.com> | 2009-07-30 01:41:06 +0400 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-07-30 20:45:43 +0400 |
commit | ef12379f205bed7e92434e12ddd44e62d13bebe1 (patch) | |
tree | c372f5741826e7fbdaec8eac86191b52e3e621af /arch/arm/mach-ep93xx/core.c | |
parent | 3aa7a9a3cf8774f6701b1903a6353f9545f561ce (diff) | |
download | linux-ef12379f205bed7e92434e12ddd44e62d13bebe1.tar.xz |
ARM: 5628/1: ep93xx: Introduce Pulse Width Modulator (PWM) driver
The EP93xx features two PWMs (one on the EP9307) with the following
features:
* Configurable dual output
* Separate input clocks for each PWM output
* 16-bit resolution
* Programmable pulse width (duty cycle), interval (frequency), and
polarity
This adds the necessary core support as well as the driver. A sysfs
interface is provided to control the PWM outputs.
Signed-off-by: Matthieu Crapet <mcrapet@gmail.com>
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-ep93xx/core.c')
-rw-r--r-- | arch/arm/mach-ep93xx/core.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c index 2b58df0184c1..40755298fa33 100644 --- a/arch/arm/mach-ep93xx/core.c +++ b/arch/arm/mach-ep93xx/core.c @@ -597,6 +597,91 @@ static struct platform_device ep93xx_leds = { }; +/************************************************************************* + * EP93xx pwm peripheral handling + *************************************************************************/ +static struct resource ep93xx_pwm0_resource[] = { + { + .start = EP93XX_PWM_PHYS_BASE, + .end = EP93XX_PWM_PHYS_BASE + 0x10 - 1, + .flags = IORESOURCE_MEM, + }, +}; + +static struct platform_device ep93xx_pwm0_device = { + .name = "ep93xx-pwm", + .id = 0, + .num_resources = ARRAY_SIZE(ep93xx_pwm0_resource), + .resource = ep93xx_pwm0_resource, +}; + +static struct resource ep93xx_pwm1_resource[] = { + { + .start = EP93XX_PWM_PHYS_BASE + 0x20, + .end = EP93XX_PWM_PHYS_BASE + 0x30 - 1, + .flags = IORESOURCE_MEM, + }, +}; + +static struct platform_device ep93xx_pwm1_device = { + .name = "ep93xx-pwm", + .id = 1, + .num_resources = ARRAY_SIZE(ep93xx_pwm1_resource), + .resource = ep93xx_pwm1_resource, +}; + +void __init ep93xx_register_pwm(int pwm0, int pwm1) +{ + if (pwm0) + platform_device_register(&ep93xx_pwm0_device); + + /* NOTE: EP9307 does not have PWMOUT1 (pin EGPIO14) */ + if (pwm1) + platform_device_register(&ep93xx_pwm1_device); +} + +int ep93xx_pwm_acquire_gpio(struct platform_device *pdev) +{ + int err; + + if (pdev->id == 0) { + err = 0; + } else if (pdev->id == 1) { + err = gpio_request(EP93XX_GPIO_LINE_EGPIO14, + dev_name(&pdev->dev)); + if (err) + return err; + err = gpio_direction_output(EP93XX_GPIO_LINE_EGPIO14, 0); + if (err) + goto fail; + + /* PWM 1 output on EGPIO[14] */ + ep93xx_devcfg_set_bits(EP93XX_SYSCON_DEVCFG_PONG); + } else { + err = -ENODEV; + } + + return err; + +fail: + gpio_free(EP93XX_GPIO_LINE_EGPIO14); + return err; +} +EXPORT_SYMBOL(ep93xx_pwm_acquire_gpio); + +void ep93xx_pwm_release_gpio(struct platform_device *pdev) +{ + if (pdev->id == 1) { + gpio_direction_input(EP93XX_GPIO_LINE_EGPIO14); + gpio_free(EP93XX_GPIO_LINE_EGPIO14); + + /* EGPIO[14] used for GPIO */ + ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_PONG); + } +} +EXPORT_SYMBOL(ep93xx_pwm_release_gpio); + + extern void ep93xx_gpio_init(void); void __init ep93xx_init_devices(void) |