| Message ID | 20230912-topic-tps6598x_reset-v2-0-02a12e2ec50a@wolfvision.net |
|---|---|
| Headers | show |
| Series | usb: typec: tps6598x: add reset gpio support | expand |
On Fri, Sep 15, 2023 at 02:23:48PM +0200, Javier Carrasco wrote: > The TPS6598x PD controller provides an active-high hardware reset input > that reinitializes all device settings. If it is not grounded by > design, the driver must be able to de-assert it in order to initialize > the device. > > The PD controller is not ready for registration right after the reset > de-assertion and a delay must be introduced in that case. According to > TI, the delay can reach up to 1000 ms [1], which is in line with the > experimental results obtained with a TPS65987D. > > Add a GPIO descriptor for the reset signal and basic reset management > for initialization and suspend/resume. > > [1] https://e2e.ti.com/support/power-management-group/power-management/ > f/power-management-forum/1269856/tps65987d-tps65987d-reset-de-assert- > to-normal-operation/4809389#4809389 > > Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net> > Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> > --- > drivers/usb/typec/tipd/core.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c > index 37b56ce75f39..3068ef300073 100644 > --- a/drivers/usb/typec/tipd/core.c > +++ b/drivers/usb/typec/tipd/core.c > @@ -8,6 +8,7 @@ > > #include <linux/i2c.h> > #include <linux/acpi.h> > +#include <linux/gpio/consumer.h> > #include <linux/module.h> > #include <linux/of.h> > #include <linux/power_supply.h> > @@ -43,6 +44,9 @@ > /* TPS_REG_SYSTEM_CONF bits */ > #define TPS_SYSCONF_PORTINFO(c) ((c) & 7) > > +/* reset de-assertion to ready for operation */ > +#define SETUP_MS 1000 > + > enum { > TPS_PORTINFO_SINK, > TPS_PORTINFO_SINK_ACCESSORY, > @@ -86,6 +90,7 @@ struct tps6598x { > struct mutex lock; /* device lock */ > u8 i2c_protocol:1; > > + struct gpio_desc *reset; > struct typec_port *port; > struct typec_partner *partner; > struct usb_pd_identity partner_identity; > @@ -717,6 +722,13 @@ static int tps6598x_probe(struct i2c_client *client) > mutex_init(&tps->lock); > tps->dev = &client->dev; > > + tps->reset = devm_gpiod_get_optional(tps->dev, "reset", GPIOD_OUT_LOW); > + if (IS_ERR(tps->reset)) > + return dev_err_probe(tps->dev, PTR_ERR(tps->reset), > + "failed to get reset GPIO\n"); > + if (tps->reset) > + msleep(SETUP_MS); > + > tps->regmap = devm_regmap_init_i2c(client, &tps6598x_regmap_config); > if (IS_ERR(tps->regmap)) > return PTR_ERR(tps->regmap); > @@ -892,6 +904,9 @@ static void tps6598x_remove(struct i2c_client *client) > tps6598x_disconnect(tps, 0); > typec_unregister_port(tps->port); > usb_role_switch_put(tps->role_sw); > + > + if (tps->reset) > + gpiod_set_value_cansleep(tps->reset, 1); Do you need that "if (tps->reset)" in this case? That function is NULL safe, right? > } > > static int __maybe_unused tps6598x_suspend(struct device *dev) > @@ -902,6 +917,8 @@ static int __maybe_unused tps6598x_suspend(struct device *dev) > if (tps->wakeup) { > disable_irq(client->irq); > enable_irq_wake(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 1); > } > > if (!client->irq) > @@ -918,6 +935,9 @@ static int __maybe_unused tps6598x_resume(struct device *dev) > if (tps->wakeup) { > disable_irq_wake(client->irq); > enable_irq(client->irq); > + } else if (tps->reset) { > + gpiod_set_value_cansleep(tps->reset, 0); > + msleep(SETUP_MS); > } > > if (!client->irq) > > -- > 2.39.2 thanks,
Hi, On Fri, Sep 15, 2023 at 03:17:28PM +0200, Javier Carrasco wrote: > On 15.09.23 14:57, Heikki Krogerus wrote: > > On Fri, Sep 15, 2023 at 02:23:48PM +0200, Javier Carrasco wrote: > >> The TPS6598x PD controller provides an active-high hardware reset input > >> that reinitializes all device settings. If it is not grounded by > >> design, the driver must be able to de-assert it in order to initialize > >> the device. > >> > >> The PD controller is not ready for registration right after the reset > >> de-assertion and a delay must be introduced in that case. According to > >> TI, the delay can reach up to 1000 ms [1], which is in line with the > >> experimental results obtained with a TPS65987D. > >> > >> Add a GPIO descriptor for the reset signal and basic reset management > >> for initialization and suspend/resume. > >> > >> [1] https://e2e.ti.com/support/power-management-group/power-management/ > >> f/power-management-forum/1269856/tps65987d-tps65987d-reset-de-assert- > >> to-normal-operation/4809389#4809389 > >> > >> Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net> > >> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > >> --- > >> drivers/usb/typec/tipd/core.c | 20 ++++++++++++++++++++ > >> 1 file changed, 20 insertions(+) > >> > >> diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c > >> index 37b56ce75f39..3068ef300073 100644 > >> --- a/drivers/usb/typec/tipd/core.c > >> +++ b/drivers/usb/typec/tipd/core.c > >> @@ -8,6 +8,7 @@ > >> > >> #include <linux/i2c.h> > >> #include <linux/acpi.h> > >> +#include <linux/gpio/consumer.h> > >> #include <linux/module.h> > >> #include <linux/of.h> > >> #include <linux/power_supply.h> > >> @@ -43,6 +44,9 @@ > >> /* TPS_REG_SYSTEM_CONF bits */ > >> #define TPS_SYSCONF_PORTINFO(c) ((c) & 7) > >> > >> +/* reset de-assertion to ready for operation */ > >> +#define SETUP_MS 1000 > >> + > >> enum { > >> TPS_PORTINFO_SINK, > >> TPS_PORTINFO_SINK_ACCESSORY, > >> @@ -86,6 +90,7 @@ struct tps6598x { > >> struct mutex lock; /* device lock */ > >> u8 i2c_protocol:1; > >> > >> + struct gpio_desc *reset; > >> struct typec_port *port; > >> struct typec_partner *partner; > >> struct usb_pd_identity partner_identity; > >> @@ -717,6 +722,13 @@ static int tps6598x_probe(struct i2c_client *client) > >> mutex_init(&tps->lock); > >> tps->dev = &client->dev; > >> > >> + tps->reset = devm_gpiod_get_optional(tps->dev, "reset", GPIOD_OUT_LOW); > >> + if (IS_ERR(tps->reset)) > >> + return dev_err_probe(tps->dev, PTR_ERR(tps->reset), > >> + "failed to get reset GPIO\n"); > >> + if (tps->reset) > >> + msleep(SETUP_MS); > >> + > >> tps->regmap = devm_regmap_init_i2c(client, &tps6598x_regmap_config); > >> if (IS_ERR(tps->regmap)) > >> return PTR_ERR(tps->regmap); > >> @@ -892,6 +904,9 @@ static void tps6598x_remove(struct i2c_client *client) > >> tps6598x_disconnect(tps, 0); > >> typec_unregister_port(tps->port); > >> usb_role_switch_put(tps->role_sw); > >> + > >> + if (tps->reset) > >> + gpiod_set_value_cansleep(tps->reset, 1); > > > > Do you need that "if (tps->reset)" in this case? That function is NULL safe, > > right? > > > The function makes use of the VALIDATE_DESC_VOID macro to make it NULL > safe, but this macro also calls pr_warn if the descriptor is NULL and I > do not want to add warnings for an optional property that did not exist > before because it could be confusing. But if that is the desired > behavior, I will remove the checks. No, I don't want noise either. > >> } > >> > >> static int __maybe_unused tps6598x_suspend(struct device *dev) > >> @@ -902,6 +917,8 @@ static int __maybe_unused tps6598x_suspend(struct device *dev) > >> if (tps->wakeup) { > >> disable_irq(client->irq); > >> enable_irq_wake(client->irq); > >> + } else if (tps->reset) { > >> + gpiod_set_value_cansleep(tps->reset, 1); > >> } > >> > >> if (!client->irq) > >> @@ -918,6 +935,9 @@ static int __maybe_unused tps6598x_resume(struct device *dev) > >> if (tps->wakeup) { > >> disable_irq_wake(client->irq); > >> enable_irq(client->irq); > >> + } else if (tps->reset) { > >> + gpiod_set_value_cansleep(tps->reset, 0); > >> + msleep(SETUP_MS); > >> } > >> > >> if (!client->irq) > >> > >> -- > >> 2.39.2 thanks,
The TPS6598x PD controller provides an active-high hardware reset input that reinitializes all device settings. If it is not grounded by design, the driver must be able to de-assert it in order to initialize the device. This series adds and documents the reset signal management. It also includes the basic reset management for initialization and suspend/resume control. Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net> --- Changes in v2: - core.c: minor coding style correction ({} in 'else' after 'if {}') - ti,tps6598x.yaml: reference to the device instead of the driver in the commit message. - Link to v1: https://lore.kernel.org/r/20230912-topic-tps6598x_reset-v1-0-78dc0bf61790@wolfvision.net --- Javier Carrasco (2): usb: typec: tps6598x: add reset gpio support dt-bindings: usb: tps6598x: add reset-gpios property .../devicetree/bindings/usb/ti,tps6598x.yaml | 6 ++++++ drivers/usb/typec/tipd/core.c | 20 ++++++++++++++++++++ 2 files changed, 26 insertions(+) --- base-commit: 0bb80ecc33a8fb5a682236443c1e740d5c917d1d change-id: 20230912-topic-tps6598x_reset-55e9494e8649 Best regards,