From 333b08ee8c6e120d67118e4eb71c45f5c369c8a4 Mon Sep 17 00:00:00 2001 From: "Philip, Avinash" Date: Tue, 27 Nov 2012 14:18:09 +0530 Subject: [PATCH] pwm: tiecap: Add device-tree binding This patch 1. Add support for device-tree binding for ECAP APWM 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-tiecap.txt | 23 ++++++++++++ drivers/pwm/pwm-tiecap.c | 42 +++++++++++++++++++++- 2 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/pwm/pwm-tiecap.txt diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt new file mode 100644 index 0000000..131e8c1 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt @@ -0,0 +1,23 @@ +TI SOC ECAP based APWM controller + +Required properties: +- compatible: Must be "ti,am33xx-ecap" +- #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 ECAP: + "ecap", being the 0-based instance number from the HW spec + +Example: + +ecap0: ecap@0 { + compatible = "ti,am33xx-ecap"; + #pwm-cells = <3>; + reg = <0x48300100 0x80>; + ti,hwmods = "ecap0"; +}; diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c index d6d4cf0..0f541c5 100644 --- a/drivers/pwm/pwm-tiecap.c +++ b/drivers/pwm/pwm-tiecap.c @@ -25,6 +25,9 @@ #include #include #include +#include + +#include "pwm-tipwmss.h" /* ECAP registers and bits definitions */ #define CAP1 0x08 @@ -184,12 +187,19 @@ static const struct pwm_ops ecap_pwm_ops = { .owner = THIS_MODULE, }; +static const struct of_device_id ecap_of_match[] = { + { .compatible = "ti,am33xx-ecap" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ecap_of_match); + static int __devinit ecap_pwm_probe(struct platform_device *pdev) { int ret; struct resource *r; struct clk *clk; struct ecap_pwm_chip *pc; + u16 status; pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); if (!pc) { @@ -211,6 +221,8 @@ static int __devinit ecap_pwm_probe(struct platform_device *pdev) pc->chip.dev = &pdev->dev; pc->chip.ops = &ecap_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 = 1; @@ -231,14 +243,40 @@ static int __devinit ecap_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_ECAPCLK_EN); + if (!(status & PWMSS_ECAPCLK_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 ecap_pwm_remove(struct platform_device *pdev) { struct ecap_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_ECAPCLK_STOP_REQ); + pm_runtime_put_sync(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); return pwmchip_remove(&pc->chip); @@ -246,7 +284,9 @@ static int __devexit ecap_pwm_remove(struct platform_device *pdev) static struct platform_driver ecap_pwm_driver = { .driver = { - .name = "ecap", + .name = "ecap", + .owner = THIS_MODULE, + .of_match_table = ecap_of_match, }, .probe = ecap_pwm_probe, .remove = __devexit_p(ecap_pwm_remove), -- 2.7.4