Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751798AbdIOOFZ (ORCPT ); Fri, 15 Sep 2017 10:05:25 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:32863 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751722AbdIOOFV (ORCPT ); Fri, 15 Sep 2017 10:05:21 -0400 X-Google-Smtp-Source: AOwi7QAzIH6/hvAbIjH5zOvMcSOgiafNuls3LtckCGR5v/XnKDsOaLV8qFkRPKDf0LBNpw65e4vbNg== From: Romain Izard To: Nicolas Ferre , Alexandre Belloni , Boris Brezillon , Michael Turquette , Stephen Boyd , Ludovic Desroches , Wenyou Yang , Josh Wu , David Woodhouse , Brian Norris , Marek Vasut , Cyrille Pitchen , Thierry Reding , Richard Genoud , Greg Kroah-Hartman , Alan Stern Cc: linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-pwm@vger.kernel.org, linux-serial@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Romain Izard Subject: [PATCH v2 7/9] pwm: atmel-tcb: Support backup mode Date: Fri, 15 Sep 2017 16:04:09 +0200 Message-Id: <20170915140411.31716-8-romain.izard.pro@gmail.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170915140411.31716-1-romain.izard.pro@gmail.com> References: <20170915140411.31716-1-romain.izard.pro@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3632 Lines: 118 Save and restore registers for the PWM on suspend and resume, which makes hibernation and backup modes possible. Signed-off-by: Romain Izard --- drivers/pwm/pwm-atmel-tcb.c | 63 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 61 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c index 75db585a2a94..acd3ce8ecf3f 100644 --- a/drivers/pwm/pwm-atmel-tcb.c +++ b/drivers/pwm/pwm-atmel-tcb.c @@ -37,11 +37,20 @@ struct atmel_tcb_pwm_device { unsigned period; /* PWM period expressed in clk cycles */ }; +struct atmel_tcb_channel { + u32 enabled; + u32 cmr; + u32 ra; + u32 rb; + u32 rc; +}; + struct atmel_tcb_pwm_chip { struct pwm_chip chip; spinlock_t lock; struct atmel_tc *tc; struct atmel_tcb_pwm_device *pwms[NPWM]; + struct atmel_tcb_channel bkup[NPWM / 2]; }; static inline struct atmel_tcb_pwm_chip *to_tcb_chip(struct pwm_chip *chip) @@ -175,12 +184,15 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) * Use software trigger to apply the new setting. * If both PWM devices in this group are disabled we stop the clock. */ - if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC))) + if (!(cmr & (ATMEL_TC_ACPC | ATMEL_TC_BCPC))) { __raw_writel(ATMEL_TC_SWTRG | ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(group, CCR)); - else + tcbpwmc->bkup[group].enabled = 1; + } else { __raw_writel(ATMEL_TC_SWTRG, regs + ATMEL_TC_REG(group, CCR)); + tcbpwmc->bkup[group].enabled = 0; + } spin_unlock(&tcbpwmc->lock); } @@ -263,6 +275,7 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) /* Use software trigger to apply the new setting */ __raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, regs + ATMEL_TC_REG(group, CCR)); + tcbpwmc->bkup[group].enabled = 1; spin_unlock(&tcbpwmc->lock); return 0; } @@ -445,10 +458,56 @@ static const struct of_device_id atmel_tcb_pwm_dt_ids[] = { }; MODULE_DEVICE_TABLE(of, atmel_tcb_pwm_dt_ids); +#ifdef CONFIG_PM_SLEEP +static int atmel_tcb_pwm_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev); + void __iomem *base = tcbpwm->tc->regs; + int i; + + for (i = 0; i < (NPWM / 2); i++) { + struct atmel_tcb_channel *chan = &tcbpwm->bkup[i]; + + chan->cmr = readl(base + ATMEL_TC_REG(i, CMR)); + chan->ra = readl(base + ATMEL_TC_REG(i, RA)); + chan->rb = readl(base + ATMEL_TC_REG(i, RB)); + chan->rc = readl(base + ATMEL_TC_REG(i, RC)); + } + return 0; +} + +static int atmel_tcb_pwm_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct atmel_tcb_pwm_chip *tcbpwm = platform_get_drvdata(pdev); + void __iomem *base = tcbpwm->tc->regs; + int i; + + for (i = 0; i < (NPWM / 2); i++) { + struct atmel_tcb_channel *chan = &tcbpwm->bkup[i]; + + writel(chan->cmr, base + ATMEL_TC_REG(i, CMR)); + writel(chan->ra, base + ATMEL_TC_REG(i, RA)); + writel(chan->rb, base + ATMEL_TC_REG(i, RB)); + writel(chan->rc, base + ATMEL_TC_REG(i, RC)); + if (chan->enabled) { + writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, + base + ATMEL_TC_REG(i, CCR)); + } + } + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(atmel_tcb_pwm_pm_ops, atmel_tcb_pwm_suspend, + atmel_tcb_pwm_resume); + static struct platform_driver atmel_tcb_pwm_driver = { .driver = { .name = "atmel-tcb-pwm", .of_match_table = atmel_tcb_pwm_dt_ids, + .pm = &atmel_tcb_pwm_pm_ops, }, .probe = atmel_tcb_pwm_probe, .remove = atmel_tcb_pwm_remove, -- 2.11.0