From 53ad9e8d37031397ee141f9bf701c0fba4257b0f Mon Sep 17 00:00:00 2001 From: "Philip, Avinash" Date: Tue, 27 Nov 2012 14:18:13 +0530 Subject: pwm: tiehrpwm: Add device-tree binding This patch 1. Add support for device-tree binding for EHRWPM driver. 2. Set size of pwm-cells set to 3 to support PWM channel number, PWM period & polarity configuration from device tree. 3. Add enable/disable clock gating in PWM subsystem common config space. 4. When here set .owner member in platform_driver structure to THIS_MODULE. Signed-off-by: Philip, Avinash Cc: Grant Likely Cc: Rob Herring Cc: Rob Landley Signed-off-by: Thierry Reding --- .../devicetree/bindings/pwm/pwm-tiehrpwm.txt | 23 ++++++++++++ drivers/pwm/pwm-tiehrpwm.c | 42 +++++++++++++++++++++- 2 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt new file mode 100644 index 000000000000..4fc7079d822e --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt @@ -0,0 +1,23 @@ +TI SOC EHRPWM based PWM controller + +Required properties: +- compatible : Must be "ti,am33xx-ehrpwm" +- #pwm-cells: Should be 3. Number of cells being used to specify PWM property. + First cell specifies the per-chip index of the PWM to use, the second + cell is the period in nanoseconds and bit 0 in the third cell is used to + encode the polarity of PWM output. Set bit 0 of the third in PWM specifier + to 1 for inverse polarity & set to 0 for normal polarity. +- reg: physical base address and size of the registers map. + +Optional properties: +- ti,hwmods: Name of the hwmod associated to the EHRPWM: + "ehrpwm", being the 0-based instance number from the HW spec + +Example: + +ehrpwm0: ehrpwm@0 { + compatible = "ti,am33xx-ehrpwm"; + #pwm-cells = <3>; + reg = <0x48300200 0x100>; + ti,hwmods = "ehrpwm0"; +}; diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c index 565f96ad2787..ee7a8b3dbed9 100644 --- a/drivers/pwm/pwm-tiehrpwm.c +++ b/drivers/pwm/pwm-tiehrpwm.c @@ -25,6 +25,9 @@ #include #include #include +#include + +#include "pwm-tipwmss.h" /* EHRPWM registers and bits definitions */ @@ -399,12 +402,19 @@ static const struct pwm_ops ehrpwm_pwm_ops = { .owner = THIS_MODULE, }; +static const struct of_device_id ehrpwm_of_match[] = { + { .compatible = "ti,am33xx-ehrpwm" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ehrpwm_of_match); + static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) { int ret; struct resource *r; struct clk *clk; struct ehrpwm_pwm_chip *pc; + u16 status; pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); if (!pc) { @@ -426,6 +436,8 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) pc->chip.dev = &pdev->dev; pc->chip.ops = &ehrpwm_pwm_ops; + pc->chip.of_xlate = of_pwm_xlate_with_flags; + pc->chip.of_pwm_n_cells = 3; pc->chip.base = -1; pc->chip.npwm = NUM_PWM_CHANNEL; @@ -453,14 +465,40 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) } pm_runtime_enable(&pdev->dev); + pm_runtime_get_sync(&pdev->dev); + + status = pwmss_submodule_state_change(pdev->dev.parent, + PWMSS_EPWMCLK_EN); + if (!(status & PWMSS_EPWMCLK_EN_ACK)) { + dev_err(&pdev->dev, "PWMSS config space clock enable failed\n"); + ret = -EINVAL; + goto pwmss_clk_failure; + } + + pm_runtime_put_sync(&pdev->dev); + platform_set_drvdata(pdev, pc); return 0; + +pwmss_clk_failure: + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pwmchip_remove(&pc->chip); + return ret; } static int __devexit ehrpwm_pwm_remove(struct platform_device *pdev) { struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev); + pm_runtime_get_sync(&pdev->dev); + /* + * Due to hardware misbehaviour, acknowledge of the stop_req + * is missing. Hence checking of the status bit skipped. + */ + pwmss_submodule_state_change(pdev->dev.parent, PWMSS_EPWMCLK_STOP_REQ); + pm_runtime_put_sync(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); return pwmchip_remove(&pc->chip); @@ -468,7 +506,9 @@ static int __devexit ehrpwm_pwm_remove(struct platform_device *pdev) static struct platform_driver ehrpwm_pwm_driver = { .driver = { - .name = "ehrpwm", + .name = "ehrpwm", + .owner = THIS_MODULE, + .of_match_table = ehrpwm_of_match, }, .probe = ehrpwm_pwm_probe, .remove = __devexit_p(ehrpwm_pwm_remove), -- cgit v1.2.3-58-ga151