| Message ID | 1615288664-45034-1-git-send-email-manish.narani@xilinx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] phy: zynqmp: Handle the clock enable/disable properly | expand |
Gentle Ping! > -----Original Message----- > From: Manish Narani <manish.narani@xilinx.com> > Sent: Tuesday, March 9, 2021 4:48 PM > To: laurent.pinchart@ideasonboard.com; kishon@ti.com; vkoul@kernel.org; > Michal Simek <michals@xilinx.com> > Cc: linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org; git > <git@xilinx.com>; Manish Narani <MNARANI@xilinx.com> > Subject: [PATCH v2] phy: zynqmp: Handle the clock enable/disable properly > > The current driver is not handling the clock enable/disable operations > properly. The clocks need to be handled correctly by enabling or > disabling at appropriate places. This patch adds code to handle the > same. > > Signed-off-by: Manish Narani <manish.narani@xilinx.com> > --- > drivers/phy/xilinx/phy-zynqmp.c | 57 > ++++++++++++++++++++++++++++++++++++----- > 1 file changed, 50 insertions(+), 7 deletions(-) > > diff --git a/drivers/phy/xilinx/phy-zynqmp.c b/drivers/phy/xilinx/phy- > zynqmp.c > index 2b65f84..37fcecf 100644 > --- a/drivers/phy/xilinx/phy-zynqmp.c > +++ b/drivers/phy/xilinx/phy-zynqmp.c > @@ -219,6 +219,7 @@ struct xpsgtr_dev { > struct mutex gtr_mutex; /* mutex for locking */ > struct xpsgtr_phy phys[NUM_LANES]; > const struct xpsgtr_ssc *refclk_sscs[NUM_LANES]; > + struct clk *clk[NUM_LANES]; > bool tx_term_fix; > unsigned int saved_icm_cfg0; > unsigned int saved_icm_cfg1; > @@ -818,11 +819,15 @@ static struct phy *xpsgtr_xlate(struct device *dev, > static int __maybe_unused xpsgtr_suspend(struct device *dev) > { > struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev); > + unsigned int i; > > /* Save the snapshot ICM_CFG registers. */ > gtr_dev->saved_icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); > gtr_dev->saved_icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); > > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); > + > return 0; > } > > @@ -832,6 +837,13 @@ static int __maybe_unused xpsgtr_resume(struct > device *dev) > unsigned int icm_cfg0, icm_cfg1; > unsigned int i; > bool skip_phy_init; > + int err; > + > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) { > + err = clk_prepare_enable(gtr_dev->clk[i]); > + if (err) > + goto err_clk_put; > + } > > icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); > icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); > @@ -852,6 +864,12 @@ static int __maybe_unused xpsgtr_resume(struct > device *dev) > gtr_dev->phys[i].skip_phy_init = skip_phy_init; > > return 0; > + > +err_clk_put: > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); > + > + return err; > } > > static const struct dev_pm_ops xpsgtr_pm_ops = { > @@ -865,6 +883,7 @@ static const struct dev_pm_ops xpsgtr_pm_ops = { > static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) > { > unsigned int refclk; > + int ret; > > for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->refclk_sscs); ++refclk) { > unsigned long rate; > @@ -874,14 +893,22 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev > *gtr_dev) > > snprintf(name, sizeof(name), "ref%u", refclk); > clk = devm_clk_get_optional(gtr_dev->dev, name); > - if (IS_ERR(clk)) > - return dev_err_probe(gtr_dev->dev, PTR_ERR(clk), > - "Failed to get reference clock > %u\n", > - refclk); > + if (IS_ERR(clk)) { > + ret = dev_err_probe(gtr_dev->dev, PTR_ERR(clk), > + "Failed to get reference clock > %u\n", > + refclk); > + goto err_clk_put; > + } > > if (!clk) > continue; > > + gtr_dev->clk[refclk] = clk; > + > + ret = clk_prepare_enable(gtr_dev->clk[refclk]); > + if (ret) > + goto err_clk_put; > + > /* > * Get the spread spectrum (SSC) settings for the reference > * clock rate. > @@ -899,11 +926,18 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev > *gtr_dev) > dev_err(gtr_dev->dev, > "Invalid rate %lu for reference clock %u\n", > rate, refclk); > - return -EINVAL; > + ret = -EINVAL; > + goto err_clk_put; > } > } > > return 0; > + > +err_clk_put: > + for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->clk); refclk++) > + clk_disable_unprepare(gtr_dev->clk[refclk]); > + > + return ret; > } > > static int xpsgtr_probe(struct platform_device *pdev) > @@ -912,6 +946,7 @@ static int xpsgtr_probe(struct platform_device *pdev) > struct xpsgtr_dev *gtr_dev; > struct phy_provider *provider; > unsigned int port; > + unsigned int i; > int ret; > > gtr_dev = devm_kzalloc(&pdev->dev, sizeof(*gtr_dev), GFP_KERNEL); > @@ -951,7 +986,8 @@ static int xpsgtr_probe(struct platform_device *pdev) > phy = devm_phy_create(&pdev->dev, np, &xpsgtr_phyops); > if (IS_ERR(phy)) { > dev_err(&pdev->dev, "failed to create PHY\n"); > - return PTR_ERR(phy); > + ret = PTR_ERR(phy); > + goto err_clk_put; > } > > gtr_phy->phy = phy; > @@ -962,9 +998,16 @@ static int xpsgtr_probe(struct platform_device > *pdev) > provider = devm_of_phy_provider_register(&pdev->dev, > xpsgtr_xlate); > if (IS_ERR(provider)) { > dev_err(&pdev->dev, "registering provider failed\n"); > - return PTR_ERR(provider); > + ret = PTR_ERR(provider); > + goto err_clk_put; > } > return 0; > + > +err_clk_put: > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); > + > + return ret; > } > > static const struct of_device_id xpsgtr_of_match[] = { > -- > 2.1.1
Hi Manish, Thank you for the patch. On Tue, Mar 09, 2021 at 04:47:44PM +0530, Manish Narani wrote: > The current driver is not handling the clock enable/disable operations > properly. The clocks need to be handled correctly by enabling or > disabling at appropriate places. This patch adds code to handle the > same. > > Signed-off-by: Manish Narani <manish.narani@xilinx.com> > --- > drivers/phy/xilinx/phy-zynqmp.c | 57 ++++++++++++++++++++++++++++++++++++----- > 1 file changed, 50 insertions(+), 7 deletions(-) > > diff --git a/drivers/phy/xilinx/phy-zynqmp.c b/drivers/phy/xilinx/phy-zynqmp.c > index 2b65f84..37fcecf 100644 > --- a/drivers/phy/xilinx/phy-zynqmp.c > +++ b/drivers/phy/xilinx/phy-zynqmp.c > @@ -219,6 +219,7 @@ struct xpsgtr_dev { > struct mutex gtr_mutex; /* mutex for locking */ > struct xpsgtr_phy phys[NUM_LANES]; > const struct xpsgtr_ssc *refclk_sscs[NUM_LANES]; > + struct clk *clk[NUM_LANES]; > bool tx_term_fix; > unsigned int saved_icm_cfg0; > unsigned int saved_icm_cfg1; > @@ -818,11 +819,15 @@ static struct phy *xpsgtr_xlate(struct device *dev, > static int __maybe_unused xpsgtr_suspend(struct device *dev) > { > struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev); > + unsigned int i; > > /* Save the snapshot ICM_CFG registers. */ > gtr_dev->saved_icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); > gtr_dev->saved_icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); > > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); > + > return 0; > } > > @@ -832,6 +837,13 @@ static int __maybe_unused xpsgtr_resume(struct device *dev) > unsigned int icm_cfg0, icm_cfg1; > unsigned int i; > bool skip_phy_init; > + int err; > + > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) { > + err = clk_prepare_enable(gtr_dev->clk[i]); > + if (err) > + goto err_clk_put; > + } > > icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); > icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); > @@ -852,6 +864,12 @@ static int __maybe_unused xpsgtr_resume(struct device *dev) > gtr_dev->phys[i].skip_phy_init = skip_phy_init; > > return 0; > + > +err_clk_put: > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); You should only disable the clocks that have been successfully enabled. Something like this should do: while (i-- > 0) clk_disable_unprepare(gtr_dev->clk[i]); > + > + return err; > } > > static const struct dev_pm_ops xpsgtr_pm_ops = { > @@ -865,6 +883,7 @@ static const struct dev_pm_ops xpsgtr_pm_ops = { > static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) > { > unsigned int refclk; > + int ret; > > for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->refclk_sscs); ++refclk) { > unsigned long rate; > @@ -874,14 +893,22 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) > > snprintf(name, sizeof(name), "ref%u", refclk); > clk = devm_clk_get_optional(gtr_dev->dev, name); > - if (IS_ERR(clk)) > - return dev_err_probe(gtr_dev->dev, PTR_ERR(clk), > - "Failed to get reference clock %u\n", > - refclk); > + if (IS_ERR(clk)) { > + ret = dev_err_probe(gtr_dev->dev, PTR_ERR(clk), > + "Failed to get reference clock %u\n", > + refclk); > + goto err_clk_put; > + } > > if (!clk) > continue; > > + gtr_dev->clk[refclk] = clk; > + > + ret = clk_prepare_enable(gtr_dev->clk[refclk]); > + if (ret) > + goto err_clk_put; > + > /* > * Get the spread spectrum (SSC) settings for the reference > * clock rate. > @@ -899,11 +926,18 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) > dev_err(gtr_dev->dev, > "Invalid rate %lu for reference clock %u\n", > rate, refclk); > - return -EINVAL; > + ret = -EINVAL; > + goto err_clk_put; > } > } > > return 0; > + > +err_clk_put: > + for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->clk); refclk++) > + clk_disable_unprepare(gtr_dev->clk[refclk]); Here too you will disable a clock that hasn't been enabled if clk_prepare_enable() failed. Clocks that haven't been retrieved at all are fine, as clk_disable_unprepare() can be safely called with a NULL pointer. This could be fixed by replacing the code above with ret = clk_prepare_enable(clk); if (ret) goto err_clk_put; gtr_dev->clk[refclk] = clk; > + > + return ret; > } > > static int xpsgtr_probe(struct platform_device *pdev) > @@ -912,6 +946,7 @@ static int xpsgtr_probe(struct platform_device *pdev) > struct xpsgtr_dev *gtr_dev; > struct phy_provider *provider; > unsigned int port; > + unsigned int i; > int ret; > > gtr_dev = devm_kzalloc(&pdev->dev, sizeof(*gtr_dev), GFP_KERNEL); > @@ -951,7 +986,8 @@ static int xpsgtr_probe(struct platform_device *pdev) > phy = devm_phy_create(&pdev->dev, np, &xpsgtr_phyops); > if (IS_ERR(phy)) { > dev_err(&pdev->dev, "failed to create PHY\n"); > - return PTR_ERR(phy); > + ret = PTR_ERR(phy); > + goto err_clk_put; > } > > gtr_phy->phy = phy; > @@ -962,9 +998,16 @@ static int xpsgtr_probe(struct platform_device *pdev) > provider = devm_of_phy_provider_register(&pdev->dev, xpsgtr_xlate); > if (IS_ERR(provider)) { > dev_err(&pdev->dev, "registering provider failed\n"); > - return PTR_ERR(provider); > + ret = PTR_ERR(provider); > + goto err_clk_put; > } > return 0; > + > +err_clk_put: > + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) > + clk_disable_unprepare(gtr_dev->clk[i]); > + > + return ret; > } > > static const struct of_device_id xpsgtr_of_match[] = {
diff --git a/drivers/phy/xilinx/phy-zynqmp.c b/drivers/phy/xilinx/phy-zynqmp.c index 2b65f84..37fcecf 100644 --- a/drivers/phy/xilinx/phy-zynqmp.c +++ b/drivers/phy/xilinx/phy-zynqmp.c @@ -219,6 +219,7 @@ struct xpsgtr_dev { struct mutex gtr_mutex; /* mutex for locking */ struct xpsgtr_phy phys[NUM_LANES]; const struct xpsgtr_ssc *refclk_sscs[NUM_LANES]; + struct clk *clk[NUM_LANES]; bool tx_term_fix; unsigned int saved_icm_cfg0; unsigned int saved_icm_cfg1; @@ -818,11 +819,15 @@ static struct phy *xpsgtr_xlate(struct device *dev, static int __maybe_unused xpsgtr_suspend(struct device *dev) { struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev); + unsigned int i; /* Save the snapshot ICM_CFG registers. */ gtr_dev->saved_icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); gtr_dev->saved_icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) + clk_disable_unprepare(gtr_dev->clk[i]); + return 0; } @@ -832,6 +837,13 @@ static int __maybe_unused xpsgtr_resume(struct device *dev) unsigned int icm_cfg0, icm_cfg1; unsigned int i; bool skip_phy_init; + int err; + + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) { + err = clk_prepare_enable(gtr_dev->clk[i]); + if (err) + goto err_clk_put; + } icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0); icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1); @@ -852,6 +864,12 @@ static int __maybe_unused xpsgtr_resume(struct device *dev) gtr_dev->phys[i].skip_phy_init = skip_phy_init; return 0; + +err_clk_put: + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) + clk_disable_unprepare(gtr_dev->clk[i]); + + return err; } static const struct dev_pm_ops xpsgtr_pm_ops = { @@ -865,6 +883,7 @@ static const struct dev_pm_ops xpsgtr_pm_ops = { static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) { unsigned int refclk; + int ret; for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->refclk_sscs); ++refclk) { unsigned long rate; @@ -874,14 +893,22 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) snprintf(name, sizeof(name), "ref%u", refclk); clk = devm_clk_get_optional(gtr_dev->dev, name); - if (IS_ERR(clk)) - return dev_err_probe(gtr_dev->dev, PTR_ERR(clk), - "Failed to get reference clock %u\n", - refclk); + if (IS_ERR(clk)) { + ret = dev_err_probe(gtr_dev->dev, PTR_ERR(clk), + "Failed to get reference clock %u\n", + refclk); + goto err_clk_put; + } if (!clk) continue; + gtr_dev->clk[refclk] = clk; + + ret = clk_prepare_enable(gtr_dev->clk[refclk]); + if (ret) + goto err_clk_put; + /* * Get the spread spectrum (SSC) settings for the reference * clock rate. @@ -899,11 +926,18 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) dev_err(gtr_dev->dev, "Invalid rate %lu for reference clock %u\n", rate, refclk); - return -EINVAL; + ret = -EINVAL; + goto err_clk_put; } } return 0; + +err_clk_put: + for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->clk); refclk++) + clk_disable_unprepare(gtr_dev->clk[refclk]); + + return ret; } static int xpsgtr_probe(struct platform_device *pdev) @@ -912,6 +946,7 @@ static int xpsgtr_probe(struct platform_device *pdev) struct xpsgtr_dev *gtr_dev; struct phy_provider *provider; unsigned int port; + unsigned int i; int ret; gtr_dev = devm_kzalloc(&pdev->dev, sizeof(*gtr_dev), GFP_KERNEL); @@ -951,7 +986,8 @@ static int xpsgtr_probe(struct platform_device *pdev) phy = devm_phy_create(&pdev->dev, np, &xpsgtr_phyops); if (IS_ERR(phy)) { dev_err(&pdev->dev, "failed to create PHY\n"); - return PTR_ERR(phy); + ret = PTR_ERR(phy); + goto err_clk_put; } gtr_phy->phy = phy; @@ -962,9 +998,16 @@ static int xpsgtr_probe(struct platform_device *pdev) provider = devm_of_phy_provider_register(&pdev->dev, xpsgtr_xlate); if (IS_ERR(provider)) { dev_err(&pdev->dev, "registering provider failed\n"); - return PTR_ERR(provider); + ret = PTR_ERR(provider); + goto err_clk_put; } return 0; + +err_clk_put: + for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) + clk_disable_unprepare(gtr_dev->clk[i]); + + return ret; } static const struct of_device_id xpsgtr_of_match[] = {
The current driver is not handling the clock enable/disable operations properly. The clocks need to be handled correctly by enabling or disabling at appropriate places. This patch adds code to handle the same. Signed-off-by: Manish Narani <manish.narani@xilinx.com> --- drivers/phy/xilinx/phy-zynqmp.c | 57 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 50 insertions(+), 7 deletions(-)