From d91861dafda44d808272f55758ca91d962feda6e Mon Sep 17 00:00:00 2001 From: "Philip, Avinash" Date: Tue, 27 Nov 2012 14:18:12 +0530 Subject: pwm: pwm-tiehrpwm: Adding TBCLK gating support. Some platforms (like AM33XX) requires clock gating from control module explicitly for TBCLK. Enabling of this clock required for the functioning of the time base sub module in EHRPWM module. Adding support for handling by enabling the clock on PWM device enable & disable on PWM device disable. Platforms don't have explicit TBCLK gating has to add dummy TBCLK node. Signed-off-by: Philip, Avinash Signed-off-by: Thierry Reding diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c index d3c1dff..565f96a 100644 --- a/drivers/pwm/pwm-tiehrpwm.c +++ b/drivers/pwm/pwm-tiehrpwm.c @@ -115,6 +115,7 @@ struct ehrpwm_pwm_chip { void __iomem *mmio_base; unsigned long period_cycles[NUM_PWM_CHANNEL]; enum pwm_polarity polarity[NUM_PWM_CHANNEL]; + struct clk *tbclk; }; static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip) @@ -335,6 +336,9 @@ static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) /* Channels polarity can be configured from action qualifier module */ configure_polarity(pc, pwm->hwpwm); + /* Enable TBCLK before enabling PWM device */ + clk_enable(pc->tbclk); + /* Enable time counter for free_run */ ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN); return 0; @@ -363,6 +367,9 @@ static void ehrpwm_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val); + /* Disabling TBCLK on PWM disable */ + clk_disable(pc->tbclk); + /* Stop Time base counter */ ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_STOP_NEXT); @@ -432,6 +439,13 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev) if (!pc->mmio_base) return -EADDRNOTAVAIL; + /* Acquire tbclk for Time Base EHRPWM submodule */ + pc->tbclk = devm_clk_get(&pdev->dev, "tbclk"); + if (IS_ERR(pc->tbclk)) { + dev_err(&pdev->dev, "Failed to get tbclk\n"); + return PTR_ERR(pc->tbclk); + } + ret = pwmchip_add(&pc->chip); if (ret < 0) { dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); -- cgit v0.10.2