From 82aff048dde444334c7045fab620b13058ff15a7 Mon Sep 17 00:00:00 2001 From: Vladimir Zapolskiy Date: Sun, 6 Dec 2015 13:32:00 +0200 Subject: [PATCH] pwm: lpc32xx: make device usable with common clock framework As a preparatory change for switching LPC32xx mach support to common clock framework fix clk_enable/clk_disable calls without matching clk_prepare/clk_unprepare. The driver can not be used on a platform with common clock framework until clk_prepare/clk_unprepare calls are added, otherwise clk_enable calls will fail and a WARN is generated: # echo 1 > /sys/bus/platform/drivers/lpc32xx-pwm/4005c000.pwm/pwm/pwmchip0/pwm0/enable ------------[ cut here ]------------ WARNING: CPU: 0 PID: 701 at drivers/clk/clk.c:727 clk_core_enable+0x2c/0xa4() Modules linked in: sc16is7xx CPU: 0 PID: 701 Comm: sh Tainted: G W 4.3.0-rc2+ #171 Hardware name: LPC32XX SoC (Flattened Device Tree) Backtrace: [<>] (dump_backtrace) from [<>] (show_stack+0x18/0x1c) [<>] (show_stack) from [<>] (dump_stack+0x20/0x28) [<>] (dump_stack) from [<>] (warn_slowpath_common+0x90/0xb8) [<>] (warn_slowpath_common) from [<>] (warn_slowpath_null+0x24/0x2c) [<>] (warn_slowpath_null) from [<>] (clk_core_enable+0x2c/0xa4) [<>] (clk_core_enable) from [<>] (clk_enable+0x24/0x38) [<>] (clk_enable) from [<>] (lpc32xx_pwm_enable+0x1c/0x40) [<>] (lpc32xx_pwm_enable) from [<>] (pwm_enable+0x48/0x5c) [<>] (pwm_enable) from [<>] (pwm_enable_store+0x5c/0x78) [<>] (pwm_enable_store) from [<>] (dev_attr_store+0x20/0x2c) [<>] (dev_attr_store) from [<>] (sysfs_kf_write+0x44/0x50) [<>] (sysfs_kf_write) from [<>] (kernfs_fop_write+0x134/0x194) [<>] (kernfs_fop_write) from [<>] (__vfs_write+0x34/0xdc) [<>] (__vfs_write) from [<>] (vfs_write+0xb8/0x140) [<>] (vfs_write) from [<>] (SyS_write+0x50/0x90) [<>] (SyS_write) from [<>] (ret_fast_syscall+0x0/0x38) Signed-off-by: Vladimir Zapolskiy Signed-off-by: Thierry Reding --- drivers/pwm/pwm-lpc32xx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c index ce8ab202be8b..63468a872ca7 100644 --- a/drivers/pwm/pwm-lpc32xx.c +++ b/drivers/pwm/pwm-lpc32xx.c @@ -83,7 +83,7 @@ static int lpc32xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) u32 val; int ret; - ret = clk_enable(lpc32xx->clk); + ret = clk_prepare_enable(lpc32xx->clk); if (ret) return ret; @@ -103,7 +103,7 @@ static void lpc32xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) val &= ~PWM_ENABLE; writel(val, lpc32xx->base + (pwm->hwpwm << 2)); - clk_disable(lpc32xx->clk); + clk_disable_unprepare(lpc32xx->clk); } static const struct pwm_ops lpc32xx_pwm_ops = { -- 2.20.1