From: Boris Brezillon <[email protected]> Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang") added a workaround for the slow clock as it is not properly handled by its users.
Get and use the slow clock as it is necessary for the timer counters. Signed-off-by: Boris Brezillon <[email protected]> Signed-off-by: Alexandre Belloni <[email protected]> --- Cc: Daniel Lezcano <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Thierry Reding <[email protected]> Cc: [email protected] drivers/clocksource/tcb_clksrc.c | 8 ++++++++ drivers/misc/atmel_tclib.c | 4 ++++ drivers/pwm/pwm-atmel-tcb.c | 23 ++++++++++++++++------- include/linux/atmel_tc.h | 1 + 4 files changed, 29 insertions(+), 7 deletions(-) diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c index b9b7277173c2..969ba03633b0 100644 --- a/drivers/clocksource/tcb_clksrc.c +++ b/drivers/clocksource/tcb_clksrc.c @@ -188,6 +188,13 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) ret = clk_prepare_enable(t2_clk); if (ret) return ret; + + ret = clk_prepare_enable(tc->slow_clk); + if (ret) { + clk_disable_unprepare(t2_clk); + return ret; + } + clk_disable(t2_clk); clkevt.regs = tc->regs; @@ -200,6 +207,7 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) ret = request_irq(irq, ch2_irq, IRQF_TIMER, "tc_clkevt", &clkevt); if (ret) { clk_unprepare(t2_clk); + clk_disable_unprepare(tc->slow_clk); return ret; } diff --git a/drivers/misc/atmel_tclib.c b/drivers/misc/atmel_tclib.c index 0ca05c3ec8d6..ac24a4bd63f7 100644 --- a/drivers/misc/atmel_tclib.c +++ b/drivers/misc/atmel_tclib.c @@ -125,6 +125,10 @@ static int __init tc_probe(struct platform_device *pdev) if (IS_ERR(clk)) return PTR_ERR(clk); + tc->slow_clk = devm_clk_get(&pdev->dev, "slow_clk"); + if (IS_ERR(tc->slow_clk)) + return PTR_ERR(tc->slow_clk); + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); tc->regs = devm_ioremap_resource(&pdev->dev, r); if (IS_ERR(tc->regs)) diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c index d14e0677c92d..070a32a35295 100644 --- a/drivers/pwm/pwm-atmel-tcb.c +++ b/drivers/pwm/pwm-atmel-tcb.c @@ -305,7 +305,7 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, */ if (i == 5) { i = slowclk; - rate = 32768; + rate = clk_get_rate(tc->slow_clk); min = div_u64(NSEC_PER_SEC, rate); max = min << tc->tcb_config->counter_width; @@ -387,9 +387,9 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev) tcbpwm = devm_kzalloc(&pdev->dev, sizeof(*tcbpwm), GFP_KERNEL); if (tcbpwm == NULL) { - atmel_tc_free(tc); + err = -ENOMEM; dev_err(&pdev->dev, "failed to allocate memory\n"); - return -ENOMEM; + goto err_free_tc; } tcbpwm->chip.dev = &pdev->dev; @@ -400,17 +400,24 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev) tcbpwm->chip.npwm = NPWM; tcbpwm->tc = tc; + err = clk_prepare_enable(tc->slow_clk); + if (err) + goto err_free_tc; + spin_lock_init(&tcbpwm->lock); err = pwmchip_add(&tcbpwm->chip); - if (err < 0) { - atmel_tc_free(tc); - return err; - } + if (err < 0) + goto err_free_tc; platform_set_drvdata(pdev, tcbpwm); return 0; + +err_free_tc: + atmel_tc_free(tc); + + return err; } static int atmel_tcb_pwm_remove(struct platform_device *pdev) @@ -418,6 +425,8 @@ static int atmel_tcb_pwm_remove(struct platform_device *pdev) struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev); int err; + clk_disable_unprepare(tcbpwm->tc->slow_clk); + err = pwmchip_remove(&tcbpwm->chip); if (err < 0) return err; diff --git a/include/linux/atmel_tc.h b/include/linux/atmel_tc.h index b87c1c7c242a..468fdfa643f0 100644 --- a/include/linux/atmel_tc.h +++ b/include/linux/atmel_tc.h @@ -67,6 +67,7 @@ struct atmel_tc { const struct atmel_tcb_config *tcb_config; int irq[3]; struct clk *clk[3]; + struct clk *slow_clk; struct list_head node; bool allocated; }; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
