Message ID | 20240822152801.602318-11-claudiu.beznea.uj@bp.renesas.com |
---|---|
State | New |
Headers | show |
Series | Add initial USB support for the Renesas RZ/G3S SoC | expand |
Hi Claudiu, > -----Original Message----- > From: claudiu beznea <claudiu.beznea@tuxon.dev> > Sent: Friday, August 23, 2024 9:58 AM - > clk@vger.kernel.org; linux-pm@vger.kernel.org; Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> > Subject: Re: [PATCH 10/16] phy: renesas: rcar-gen3-usb2: Add support to initialize the bus > > Hi, Biju, > > On 23.08.2024 10:35, Biju Das wrote: > > Hi Claudiu, > > > >> -----Original Message----- > >> From: Claudiu <claudiu.beznea@tuxon.dev> > >> Sent: Thursday, August 22, 2024 4:28 PM > >> Subject: [PATCH 10/16] phy: renesas: rcar-gen3-usb2: Add support to > >> initialize the bus > >> > >> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> > >> > >> The Renesas RZ/G3S need to initialize the USB BUS before transferring data due to hardware > limitation. > >> As the register that need to be touched for this is in the address > >> space of the USB PHY, and the UBS PHY need to be initialized before > >> any other USB drivers handling data transfer, add support to initialize the USB BUS. > >> > >> As the USB PHY is probed before any other USB drivers that enables > >> clocks and de-assert the reset signals and the BUS initialization is > >> done in the probe phase, we need to add code to de-assert reset signal and runtime resume the > device (which enables its clocks) before accessing the registers. > >> > >> As the reset signals are not required by the USB PHY driver for the > >> other USB PHY hardware variants, the reset signals and runtime PM was handled only in the function > that initialize the USB BUS. > >> > >> The PHY initialization was done right after runtime PM enable to have > >> all in place when the PHYs are registered. > > > > There is no user for this patch. The first user is RZ/G3S and you > > should merge this patch with next one. > > I think this is a matter of taste... This is how I usually format the patches (for scenarios like > this) and got no request for squashing. That is strange for trivial patches like this. Cheers, Biju > > > >> > >> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> > >> --- > >> drivers/phy/renesas/phy-rcar-gen3-usb2.c | 50 > >> ++++++++++++++++++++++-- > >> 1 file changed, 47 insertions(+), 3 deletions(-) > >> > >> diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c > >> b/drivers/phy/renesas/phy-rcar-gen3-usb2.c > >> index 7594f64eb737..cf4299cea579 100644 > >> --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c > >> +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c > >> @@ -19,12 +19,14 @@ > >> #include <linux/platform_device.h> > >> #include <linux/pm_runtime.h> > >> #include <linux/regulator/consumer.h> > >> +#include <linux/reset.h> > >> #include <linux/string.h> > >> #include <linux/usb/of.h> > >> #include <linux/workqueue.h> > >> > >> /******* USB2.0 Host registers (original offset is +0x200) *******/ > >> #define USB2_INT_ENABLE 0x000 > >> +#define USB2_AHB_BUS_CTR 0x008 > >> #define USB2_USBCTR 0x00c > >> #define USB2_SPD_RSM_TIMSET 0x10c > >> #define USB2_OC_TIMSET 0x110 > >> @@ -40,6 +42,10 @@ > >> #define USB2_INT_ENABLE_USBH_INTB_EN BIT(2) /* For EHCI */ > >> #define USB2_INT_ENABLE_USBH_INTA_EN BIT(1) /* For OHCI */ > >> > >> +/* AHB_BUS_CTR */ > >> +#define USB2_AHB_BUS_CTR_MBL_MASK GENMASK(1, 0) > >> +#define USB2_AHB_BUS_CTR_MBL_INCR4 2 > >> + > >> /* USBCTR */ > >> #define USB2_USBCTR_DIRPD BIT(2) > >> #define USB2_USBCTR_PLL_RST BIT(1) > >> @@ -111,6 +117,7 @@ struct rcar_gen3_chan { > >> struct extcon_dev *extcon; > >> struct rcar_gen3_phy rphys[NUM_OF_PHYS]; > >> struct regulator *vbus; > >> + struct reset_control *rstc; > >> struct work_struct work; > >> struct mutex lock; /* protects rphys[...].powered */ > >> enum usb_dr_mode dr_mode; > >> @@ -125,6 +132,7 @@ struct rcar_gen3_chan { struct rcar_gen3_phy_drv_data { > >> const struct phy_ops *phy_usb2_ops; > >> bool no_adp_ctrl; > >> + bool init_bus; > >> }; > >> > >> /* > >> @@ -650,6 +658,35 @@ static enum usb_dr_mode rcar_gen3_get_dr_mode(struct device_node *np) > >> return candidate; > >> } > >> > >> +static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan > >> +*channel) { > >> + struct device *dev = channel->dev; > >> + int ret; > >> + u32 val; > >> + > >> + channel->rstc = devm_reset_control_array_get_shared(dev); > >> + if (IS_ERR(channel->rstc)) > >> + return PTR_ERR(channel->rstc); > >> + > >> + ret = pm_runtime_resume_and_get(dev); > >> + if (ret) > >> + return ret; > >> + > >> + ret = reset_control_deassert(channel->rstc); > >> + if (ret) > >> + goto rpm_put; > >> + > >> + val = readl(channel->base + USB2_AHB_BUS_CTR); > >> + val &= ~USB2_AHB_BUS_CTR_MBL_MASK; > >> + val |= USB2_AHB_BUS_CTR_MBL_INCR4; > >> + writel(val, channel->base + USB2_AHB_BUS_CTR); > >> + > >> +rpm_put: > >> + pm_runtime_put(dev); > >> + > >> + return ret; > >> +} > >> + > >> static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) { > >> const struct rcar_gen3_phy_drv_data *phy_data; @@ -703,6 +740,15 @@ > >> static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) > >> goto error; > >> } > >> > >> + platform_set_drvdata(pdev, channel); > >> + channel->dev = dev; > >> + > >> + if (phy_data->init_bus) { > >> + ret = rcar_gen3_phy_usb2_init_bus(channel); > >> + if (ret) > >> + goto error; > >> + } > >> + > >> channel->soc_no_adp_ctrl = phy_data->no_adp_ctrl; > >> if (phy_data->no_adp_ctrl) > >> channel->obint_enable_bits = USB2_OBINT_IDCHG_EN; @@ -733,9 +779,6 > >> @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) > >> channel->vbus = NULL; > >> } > >> > >> - platform_set_drvdata(pdev, channel); > >> - channel->dev = dev; > >> - > >> provider = devm_of_phy_provider_register(dev, rcar_gen3_phy_usb2_xlate); > >> if (IS_ERR(provider)) { > >> dev_err(dev, "Failed to register PHY provider\n"); @@ -762,6 > >> +805,7 @@ static void rcar_gen3_phy_usb2_remove(struct platform_device *pdev) > >> if (channel->is_otg_channel) > >> device_remove_file(&pdev->dev, &dev_attr_role); > >> > >> + reset_control_assert(channel->rstc); > >> pm_runtime_disable(&pdev->dev); > >> }; > >> > >> -- > >> 2.39.2 > >
On 23-08-24, 09:01, Biju Das wrote: > > >> The Renesas RZ/G3S need to initialize the USB BUS before transferring data due to hardware > > limitation. > > >> As the register that need to be touched for this is in the address > > >> space of the USB PHY, and the UBS PHY need to be initialized before > > >> any other USB drivers handling data transfer, add support to initialize the USB BUS. > > >> > > >> As the USB PHY is probed before any other USB drivers that enables > > >> clocks and de-assert the reset signals and the BUS initialization is > > >> done in the probe phase, we need to add code to de-assert reset signal and runtime resume the > > device (which enables its clocks) before accessing the registers. > > >> > > >> As the reset signals are not required by the USB PHY driver for the > > >> other USB PHY hardware variants, the reset signals and runtime PM was handled only in the function > > that initialize the USB BUS. > > >> > > >> The PHY initialization was done right after runtime PM enable to have > > >> all in place when the PHYs are registered. > > > > > > There is no user for this patch. The first user is RZ/G3S and you > > > should merge this patch with next one. > > > > I think this is a matter of taste... This is how I usually format the patches (for scenarios like > > this) and got no request for squashing. > > That is strange for trivial patches like this. Splitting is better, this patch does one thing whereas the next one uses it adds in new device, i would say quite a clean approach NOTE: Don't quote the not required context while replying, it is good mail list hygiene
diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c index 7594f64eb737..cf4299cea579 100644 --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c @@ -19,12 +19,14 @@ #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/regulator/consumer.h> +#include <linux/reset.h> #include <linux/string.h> #include <linux/usb/of.h> #include <linux/workqueue.h> /******* USB2.0 Host registers (original offset is +0x200) *******/ #define USB2_INT_ENABLE 0x000 +#define USB2_AHB_BUS_CTR 0x008 #define USB2_USBCTR 0x00c #define USB2_SPD_RSM_TIMSET 0x10c #define USB2_OC_TIMSET 0x110 @@ -40,6 +42,10 @@ #define USB2_INT_ENABLE_USBH_INTB_EN BIT(2) /* For EHCI */ #define USB2_INT_ENABLE_USBH_INTA_EN BIT(1) /* For OHCI */ +/* AHB_BUS_CTR */ +#define USB2_AHB_BUS_CTR_MBL_MASK GENMASK(1, 0) +#define USB2_AHB_BUS_CTR_MBL_INCR4 2 + /* USBCTR */ #define USB2_USBCTR_DIRPD BIT(2) #define USB2_USBCTR_PLL_RST BIT(1) @@ -111,6 +117,7 @@ struct rcar_gen3_chan { struct extcon_dev *extcon; struct rcar_gen3_phy rphys[NUM_OF_PHYS]; struct regulator *vbus; + struct reset_control *rstc; struct work_struct work; struct mutex lock; /* protects rphys[...].powered */ enum usb_dr_mode dr_mode; @@ -125,6 +132,7 @@ struct rcar_gen3_chan { struct rcar_gen3_phy_drv_data { const struct phy_ops *phy_usb2_ops; bool no_adp_ctrl; + bool init_bus; }; /* @@ -650,6 +658,35 @@ static enum usb_dr_mode rcar_gen3_get_dr_mode(struct device_node *np) return candidate; } +static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel) +{ + struct device *dev = channel->dev; + int ret; + u32 val; + + channel->rstc = devm_reset_control_array_get_shared(dev); + if (IS_ERR(channel->rstc)) + return PTR_ERR(channel->rstc); + + ret = pm_runtime_resume_and_get(dev); + if (ret) + return ret; + + ret = reset_control_deassert(channel->rstc); + if (ret) + goto rpm_put; + + val = readl(channel->base + USB2_AHB_BUS_CTR); + val &= ~USB2_AHB_BUS_CTR_MBL_MASK; + val |= USB2_AHB_BUS_CTR_MBL_INCR4; + writel(val, channel->base + USB2_AHB_BUS_CTR); + +rpm_put: + pm_runtime_put(dev); + + return ret; +} + static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) { const struct rcar_gen3_phy_drv_data *phy_data; @@ -703,6 +740,15 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) goto error; } + platform_set_drvdata(pdev, channel); + channel->dev = dev; + + if (phy_data->init_bus) { + ret = rcar_gen3_phy_usb2_init_bus(channel); + if (ret) + goto error; + } + channel->soc_no_adp_ctrl = phy_data->no_adp_ctrl; if (phy_data->no_adp_ctrl) channel->obint_enable_bits = USB2_OBINT_IDCHG_EN; @@ -733,9 +779,6 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev) channel->vbus = NULL; } - platform_set_drvdata(pdev, channel); - channel->dev = dev; - provider = devm_of_phy_provider_register(dev, rcar_gen3_phy_usb2_xlate); if (IS_ERR(provider)) { dev_err(dev, "Failed to register PHY provider\n"); @@ -762,6 +805,7 @@ static void rcar_gen3_phy_usb2_remove(struct platform_device *pdev) if (channel->is_otg_channel) device_remove_file(&pdev->dev, &dev_attr_role); + reset_control_assert(channel->rstc); pm_runtime_disable(&pdev->dev); };