From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Cl=C3=A9ment=20P=C3=A9ron?= Subject: [PATCH v4 3/7] pwm: sun4i: Add an optional probe for bus clock Date: Fri, 8 Nov 2019 09:45:13 +0100 Message-ID: <20191108084517.21617-4-peron.clem@gmail.com> References: <20191108084517.21617-1-peron.clem@gmail.com> Reply-To: peron.clem-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org In-Reply-To: <20191108084517.21617-1-peron.clem-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Thierry Reding , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Rob Herring , Mark Rutland , Maxime Ripard , Chen-Yu Tsai , Philipp Zabel Cc: linux-pwm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Jernej Skrabec , =?UTF-8?q?Cl=C3=A9ment=20P=C3=A9ron?= List-Id: linux-pwm@vger.kernel.org From: Jernej Skrabec H6 PWM core needs bus clock to be enabled in order to work. Add an optional probe for it and a fallback for previous bindings without name on module clock. Signed-off-by: Jernej Skrabec Signed-off-by: Cl=C3=A9ment P=C3=A9ron --- drivers/pwm/pwm-sun4i.c | 48 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 46 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 2b9a2a78591f..a10022d6c0fd 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -78,6 +78,7 @@ struct sun4i_pwm_data { =20 struct sun4i_pwm_chip { struct pwm_chip chip; + struct clk *bus_clk; struct clk *clk; struct reset_control *rst; void __iomem *base; @@ -363,9 +364,38 @@ static int sun4i_pwm_probe(struct platform_device *pde= v) if (IS_ERR(pwm->base)) return PTR_ERR(pwm->base); =20 - pwm->clk =3D devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(pwm->clk)) + /* Get all clocks and reset line */ + pwm->clk =3D devm_clk_get_optional(&pdev->dev, "mod"); + if (IS_ERR(pwm->clk)) { + if (PTR_ERR(pwm->rst) !=3D -EPROBE_DEFER) + dev_err(&pdev->dev, "get clock failed %pe\n", + pwm->clk); return PTR_ERR(pwm->clk); + } + + /* + * Fallback for old dtbs with a single clock and no name. + * If a parent has a clock-name called "mod" whereas the + * current node is unnamed the clock reference will be + * incorrectly obtained and will not go into this fallback. + */ + if (!pwm->clk) { + pwm->clk =3D devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm->clk)) { + if (PTR_ERR(pwm->rst) !=3D -EPROBE_DEFER) + dev_err(&pdev->dev, "get clock failed %pe\n", + pwm->clk); + return PTR_ERR(pwm->clk); + } + } + + pwm->bus_clk =3D devm_clk_get_optional(&pdev->dev, "bus"); + if (IS_ERR(pwm->bus_clk)) { + if (PTR_ERR(pwm->rst) !=3D -EPROBE_DEFER) + dev_err(&pdev->dev, "get bus_clock failed %pe\n", + pwm->bus_clk); + return PTR_ERR(pwm->bus_clk); + } =20 pwm->rst =3D devm_reset_control_get_optional_shared(&pdev->dev, NULL); if (IS_ERR(pwm->rst)) { @@ -382,6 +412,17 @@ static int sun4i_pwm_probe(struct platform_device *pde= v) return ret; } =20 + /* + * We're keeping the bus clock on for the sake of simplicity. + * Actually it only needs to be on for hardware register + * accesses. + */ + ret =3D clk_prepare_enable(pwm->bus_clk); + if (ret) { + dev_err(&pdev->dev, "Cannot prepare and enable bus_clk\n"); + goto err_bus; + } + pwm->chip.dev =3D &pdev->dev; pwm->chip.ops =3D &sun4i_pwm_ops; pwm->chip.base =3D -1; @@ -402,6 +443,8 @@ static int sun4i_pwm_probe(struct platform_device *pdev= ) return 0; =20 err_pwm_add: + clk_disable_unprepare(pwm->bus_clk); +err_bus: reset_control_assert(pwm->rst); =20 return ret; @@ -416,6 +459,7 @@ static int sun4i_pwm_remove(struct platform_device *pde= v) if (ret) return ret; =20 + clk_disable_unprepare(pwm->bus_clk); reset_control_assert(pwm->rst); =20 return 0; --=20 2.20.1 --=20 You received this message because you are subscribed to the Google Groups "= linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to linux-sunxi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To view this discussion on the web, visit https://groups.google.com/d/msgid= /linux-sunxi/20191108084517.21617-4-peron.clem%40gmail.com.