kernel.git/drivers/pwm/core.c, branch linux-3.7.y

pwm: Check for negative duty-cycle and period

2012-10-05T18:56:43Z

Make sure the duty-cycle and period passed in are not negative. This should eventually be made implicit by making them unsigned. While at it, the drivers' .config() implementations can have the equivalent checks removed. Signed-off-by: Thierry Reding Cc: Shawn Guo Cc: Mark Brown Cc: Arnd Bergmann Cc: Sachin Kamat Cc: Axel Lin Cc: Kukjin Kim Cc: Jingoo Han Cc: Jonghwan Choi Cc: Sascha Hauer Cc: "Philip, Avinash" Cc: Vaibhav Bedia Acked-by: Jingoo Han

pwm: add devm_pwm_get() and devm_pwm_put()

2012-09-10T15:05:45Z

Add resource managed variants of pwm_get() and pwm_put() for convenience. Code is largely inspired by the equivalent devm functions of the regulator framework. Signed-off-by: Alexandre Courbot Signed-off-by: Thierry Reding

pwm: Add support for configuring the PWM polarity

2012-09-10T15:05:44Z

Some hardware supports inverting the polarity of the PWM signal. This commit adds support to the PWM framework to allow users of the PWM API to configure the polarity. Note that in order to reduce complexity, changing the polarity of a PWM signal is only allowed while the PWM is disabled. A practical example where this can prove useful is to simulate inversion of the duty cycle. While inversion of polarity and duty cycle are not exactly the same, the differences for most use-cases are negligible. Signed-off-by: Philip, Avinash Signed-off-by: Thierry Reding

pwm: core: Fix coding style issues

2012-08-17T12:08:26Z

Fixes the following: WARNING: line over 80 characters ERROR: spaces required around that ':' (ctx:VxW) WARNING: Prefer pr_warn(... to pr_warning(... Signed-off-by: Sachin Kamat Signed-off-by: Thierry Reding

pwm: Add missing static storage class specifiers in core.c file

2012-08-17T12:08:24Z

Fixes the following sparse warnings: drivers/pwm/core.c:152:6: warning: symbol 'of_pwmchip_add' was not declared. Should it be static? drivers/pwm/core.c:165:6: warning: symbol 'of_pwmchip_remove' was not declared. Should it be static? Signed-off-by: Sachin Kamat Signed-off-by: Thierry Reding

pwm: fix used-uninitialized warning in pwm_get()

2012-07-23T11:24:17Z

Some versions of GCC don't seem no notice that the initialization of the index variable is tied to that of the chip variable and falsely report it as potentially being used uninitialized. However, to save anybody else from tripping over this, we now initialize the index variable unconditionally. Originally-by: Stephen Warren Signed-off-by: Thierry Reding

pwm: Add device tree support

2012-06-15T10:56:57Z

This patch adds helpers to support device tree bindings for the generic PWM API. Device tree binding documentation for PWM controllers is also provided. Acked-by: Arnd Bergmann Reviewed-by: Shawn Guo Signed-off-by: Thierry Reding

pwm: Add table-based lookup for static mappings

2012-06-15T10:56:53Z

In order to get rid of the global namespace for PWM devices, this commit provides an alternative method, similar to that of the regulator or clock frameworks, for registering a static mapping for PWM devices. This works by providing a table with a provider/consumer map in the board setup code. With the new pwm_get() and pwm_put() functions available, usage of pwm_request() and pwm_free() becomes deprecated. Reviewed-by: Shawn Guo Reviewed-by: Mark Brown Signed-off-by: Thierry Reding

pwm: Add debugfs interface

2012-06-15T10:56:53Z

This commit adds a debugfs interface that can be used to list the current internal state of the PWM devices registered with the PWM framework. Reviewed-by: Mark Brown Reviewed-by: Shawn Guo Signed-off-by: Thierry Reding

pwm: Allow chips to support multiple PWMs

2012-06-15T10:56:52Z

Many PWM controllers provide access to more than a single PWM output and may even share some resource among them. Allowing a PWM chip to provide multiple PWM devices enables better sharing of those resources. As a side-effect this change allows easy integration with the device tree where a given PWM can be looked up based on the PWM chip's phandle and a corresponding index. This commit modifies the PWM core to support multiple PWMs per struct pwm_chip. It achieves this in a similar way to how gpiolib works, by allowing PWM ranges to be requested dynamically (pwm_chip.base == -1) or starting at a given offset (pwm_chip.base >= 0). A chip specifies how many PWMs it controls using the npwm member. Each of the functions in the pwm_ops structure gets an additional argument that specified the PWM number (it can be converted to a per-chip index by subtracting the chip's base). The total maximum number of PWM devices is currently fixed to 1024 while the data is actually stored in a radix tree, thus saving resources if not all of them are used. Reviewed-by: Mark Brown Reviewed-by: Shawn Guo [eric@eukrea.com: fix error handling in pwmchip_add] Signed-off-by: Eric Bénard Signed-off-by: Thierry Reding