| Message ID | Y400YXnWBdz1e/L5@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 66310b5a0fc1ccdce9a3a5e6c6a12c08e4e0b7b1 |
| Headers | show |
| Series | [v2] soc: fsl: qe: request pins non-exclusively | expand |
On Sun, Dec 04, 2022 at 03:59:29PM -0800, Dmitry Torokhov wrote: > Commit 84582f9ed090 ("soc: fsl: qe: Avoid using gpio_to_desc()") changed > qe_pin_request() to request and hold GPIO corresponding to a given pin. > Unfortunately this does not work, as fhci-hcd requests these GPIOs > first, befor calling qe_pin_request() (see before ? > drivers/usb/host/fhci-hcd.c::of_fhci_probe()). > To fix it change qe_pin_request() to request GPIOs non-exclusively, and > free them once the code determines GPIO controller and offset for each > GPIO/pin. > > Also reaching deep into gpiolib implementation is not the best idea. We > should either export gpio_chip_hwgpio() or keep converting to the global > gpio numbers space until we fix the driver to implement proper pin GPIO number > control. With or without being rebased on top of the PR that in conflict with this change, Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> (see some nit-picks below) > Fixes: 84582f9ed090 ("soc: fsl: qe: Avoid using gpio_to_desc()") > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> > --- > > v2: > > - rebased on top of soc/driver. This will conflict with > c9eb6e546a23 soc: fsl: qe: Switch to use fwnode instead of of_node > found in next, the resolution is trivial: accept > fwnode_device_is_compatible() line found in next. > - fixed leak of gpiod when gc is not found > - dropped Linus' reviewed-by as the patch changed > > drivers/soc/fsl/qe/gpio.c | 51 +++++++++++++++++-------------------- > drivers/usb/host/fhci-hcd.c | 2 +- > include/soc/fsl/qe/qe.h | 5 ++-- > 3 files changed, 28 insertions(+), 30 deletions(-) > > diff --git a/drivers/soc/fsl/qe/gpio.c b/drivers/soc/fsl/qe/gpio.c > index af9193e7e49b..1440922341d8 100644 > --- a/drivers/soc/fsl/qe/gpio.c > +++ b/drivers/soc/fsl/qe/gpio.c > @@ -13,19 +13,12 @@ > #include <linux/err.h> > #include <linux/io.h> > #include <linux/of.h> > -#include <linux/of_gpio.h> > +#include <linux/of_gpio.h> /* for of_mm_gpio_chip */ > #include <linux/gpio/consumer.h> > #include <linux/gpio/driver.h> > #include <linux/slab.h> > #include <linux/export.h> > #include <soc/fsl/qe/qe.h> > -/* > - * FIXME: this is legacy code that is accessing gpiolib internals in order > - * to implement a custom pin controller. The proper solution is to create > - * a real combined pin control and GPIO driver in drivers/pinctrl. However > - * this hack is here for legacy code reasons. > - */ > -#include "../../../gpio/gpiolib.h" > > struct qe_gpio_chip { > struct of_mm_gpio_chip mm_gc; > @@ -147,65 +140,70 @@ struct qe_pin { > * something like qe_pio_controller. Someday. > */ > struct qe_gpio_chip *controller; > - struct gpio_desc *gpiod; > int num; > }; > > /** > * qe_pin_request - Request a QE pin > - * @np: device node to get a pin from > - * @index: index of a pin in the device tree > + * @dev: device to get the pin from > + * @index: index of the pin in the device tree > * Context: non-atomic > * > * This function return qe_pin so that you could use it with the rest of > * the QE Pin Multiplexing API. > */ > -struct qe_pin *qe_pin_request(struct device_node *np, int index) > +struct qe_pin *qe_pin_request(struct device *dev, int index) > { > struct qe_pin *qe_pin; > struct gpio_chip *gc; > struct gpio_desc *gpiod; > + int gpio_num; > int err; > > qe_pin = kzalloc(sizeof(*qe_pin), GFP_KERNEL); > if (!qe_pin) { > - pr_debug("%s: can't allocate memory\n", __func__); > + dev_dbg(dev, "%s: can't allocate memory\n", __func__); > return ERR_PTR(-ENOMEM); > } > > - gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), NULL, index, GPIOD_ASIS, "qe"); > - if (IS_ERR(gpiod)) { > - err = PTR_ERR(gpiod); > - goto err0; > - } > - if (!gpiod) { > - err = -EINVAL; > + /* > + * Request gpio as nonexclusive as it was likely reserved by the GPIO > + * caller, and we are not planning on controlling it, we only need > + * the descriptor to the to the gpio chip structure. GPIO > + */ > + gpiod = gpiod_get_index(dev, NULL, index, > + GPIOD_ASIS | GPIOD_FLAGS_BIT_NONEXCLUSIVE); > + err = PTR_ERR_OR_ZERO(gpiod); > + if (err) > goto err0; > - } > + > gc = gpiod_to_chip(gpiod); > + gpio_num = desc_to_gpio(gpiod); > + /* We no longer need this descriptor */ > + gpiod_put(gpiod); > + > if (WARN_ON(!gc)) { > err = -ENODEV; > goto err0; > } > - qe_pin->gpiod = gpiod; > + > qe_pin->controller = gpiochip_get_data(gc); > /* > * FIXME: this gets the local offset on the gpio_chip so that the driver > * can manipulate pin control settings through its custom API. The real > * solution is to create a real pin control driver for this. > */ > - qe_pin->num = gpio_chip_hwgpio(gpiod); > + qe_pin->num = gpio_num - gc->base; > > if (!of_device_is_compatible(gc->of_node, "fsl,mpc8323-qe-pario-bank")) { > - pr_debug("%s: tried to get a non-qe pin\n", __func__); > - gpiod_put(gpiod); > + dev_dbg(dev, "%s: tried to get a non-qe pin\n", __func__); > err = -EINVAL; > goto err0; > } > return qe_pin; > err0: > kfree(qe_pin); > - pr_debug("%s failed with status %d\n", __func__, err); > + dev_dbg(dev, "%s failed with status %d\n", __func__, err); You can kill these __func__ in dev_dbg():s. > return ERR_PTR(err); > } > EXPORT_SYMBOL(qe_pin_request); > @@ -220,7 +218,6 @@ EXPORT_SYMBOL(qe_pin_request); > */ > void qe_pin_free(struct qe_pin *qe_pin) > { > - gpiod_put(qe_pin->gpiod); > kfree(qe_pin); > } > EXPORT_SYMBOL(qe_pin_free); > diff --git a/drivers/usb/host/fhci-hcd.c b/drivers/usb/host/fhci-hcd.c > index 95a44462bed0..1f666804fa91 100644 > --- a/drivers/usb/host/fhci-hcd.c > +++ b/drivers/usb/host/fhci-hcd.c > @@ -651,7 +651,7 @@ static int of_fhci_probe(struct platform_device *ofdev) > } > > for (j = 0; j < NUM_PINS; j++) { > - fhci->pins[j] = qe_pin_request(node, j); > + fhci->pins[j] = qe_pin_request(dev, j); > if (IS_ERR(fhci->pins[j])) { > ret = PTR_ERR(fhci->pins[j]); > dev_err(dev, "can't get pin %d: %d\n", j, ret); > diff --git a/include/soc/fsl/qe/qe.h b/include/soc/fsl/qe/qe.h > index b02e9fe69146..eb5079904cc8 100644 > --- a/include/soc/fsl/qe/qe.h > +++ b/include/soc/fsl/qe/qe.h > @@ -172,14 +172,15 @@ static inline int par_io_data_set(u8 port, u8 pin, u8 val) { return -ENOSYS; } > /* > * Pin multiplexing functions. > */ > +struct device; > struct qe_pin; > #ifdef CONFIG_QE_GPIO > -extern struct qe_pin *qe_pin_request(struct device_node *np, int index); > +extern struct qe_pin *qe_pin_request(struct device *dev, int index); > extern void qe_pin_free(struct qe_pin *qe_pin); > extern void qe_pin_set_gpio(struct qe_pin *qe_pin); > extern void qe_pin_set_dedicated(struct qe_pin *pin); > #else > -static inline struct qe_pin *qe_pin_request(struct device_node *np, int index) > +static inline struct qe_pin *qe_pin_request(struct device *dev, int index) > { > return ERR_PTR(-ENOSYS); > } > -- > 2.39.0.rc0.267.gcb52ba06e7-goog > > > -- > Dmitry
Hello: This patch was applied to soc/soc.git (for-next) by Arnd Bergmann <arnd@arndb.de>: On Sun, 4 Dec 2022 15:59:29 -0800 you wrote: > Commit 84582f9ed090 ("soc: fsl: qe: Avoid using gpio_to_desc()") changed > qe_pin_request() to request and hold GPIO corresponding to a given pin. > Unfortunately this does not work, as fhci-hcd requests these GPIOs > first, befor calling qe_pin_request() (see > drivers/usb/host/fhci-hcd.c::of_fhci_probe()). > To fix it change qe_pin_request() to request GPIOs non-exclusively, and > free them once the code determines GPIO controller and offset for each > GPIO/pin. > > [...] Here is the summary with links: - [v2] soc: fsl: qe: request pins non-exclusively https://git.kernel.org/soc/soc/c/66310b5a0fc1 You are awesome, thank you!
diff --git a/drivers/soc/fsl/qe/gpio.c b/drivers/soc/fsl/qe/gpio.c index af9193e7e49b..1440922341d8 100644 --- a/drivers/soc/fsl/qe/gpio.c +++ b/drivers/soc/fsl/qe/gpio.c @@ -13,19 +13,12 @@ #include <linux/err.h> #include <linux/io.h> #include <linux/of.h> -#include <linux/of_gpio.h> +#include <linux/of_gpio.h> /* for of_mm_gpio_chip */ #include <linux/gpio/consumer.h> #include <linux/gpio/driver.h> #include <linux/slab.h> #include <linux/export.h> #include <soc/fsl/qe/qe.h> -/* - * FIXME: this is legacy code that is accessing gpiolib internals in order - * to implement a custom pin controller. The proper solution is to create - * a real combined pin control and GPIO driver in drivers/pinctrl. However - * this hack is here for legacy code reasons. - */ -#include "../../../gpio/gpiolib.h" struct qe_gpio_chip { struct of_mm_gpio_chip mm_gc; @@ -147,65 +140,70 @@ struct qe_pin { * something like qe_pio_controller. Someday. */ struct qe_gpio_chip *controller; - struct gpio_desc *gpiod; int num; }; /** * qe_pin_request - Request a QE pin - * @np: device node to get a pin from - * @index: index of a pin in the device tree + * @dev: device to get the pin from + * @index: index of the pin in the device tree * Context: non-atomic * * This function return qe_pin so that you could use it with the rest of * the QE Pin Multiplexing API. */ -struct qe_pin *qe_pin_request(struct device_node *np, int index) +struct qe_pin *qe_pin_request(struct device *dev, int index) { struct qe_pin *qe_pin; struct gpio_chip *gc; struct gpio_desc *gpiod; + int gpio_num; int err; qe_pin = kzalloc(sizeof(*qe_pin), GFP_KERNEL); if (!qe_pin) { - pr_debug("%s: can't allocate memory\n", __func__); + dev_dbg(dev, "%s: can't allocate memory\n", __func__); return ERR_PTR(-ENOMEM); } - gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), NULL, index, GPIOD_ASIS, "qe"); - if (IS_ERR(gpiod)) { - err = PTR_ERR(gpiod); - goto err0; - } - if (!gpiod) { - err = -EINVAL; + /* + * Request gpio as nonexclusive as it was likely reserved by the + * caller, and we are not planning on controlling it, we only need + * the descriptor to the to the gpio chip structure. + */ + gpiod = gpiod_get_index(dev, NULL, index, + GPIOD_ASIS | GPIOD_FLAGS_BIT_NONEXCLUSIVE); + err = PTR_ERR_OR_ZERO(gpiod); + if (err) goto err0; - } + gc = gpiod_to_chip(gpiod); + gpio_num = desc_to_gpio(gpiod); + /* We no longer need this descriptor */ + gpiod_put(gpiod); + if (WARN_ON(!gc)) { err = -ENODEV; goto err0; } - qe_pin->gpiod = gpiod; + qe_pin->controller = gpiochip_get_data(gc); /* * FIXME: this gets the local offset on the gpio_chip so that the driver * can manipulate pin control settings through its custom API. The real * solution is to create a real pin control driver for this. */ - qe_pin->num = gpio_chip_hwgpio(gpiod); + qe_pin->num = gpio_num - gc->base; if (!of_device_is_compatible(gc->of_node, "fsl,mpc8323-qe-pario-bank")) { - pr_debug("%s: tried to get a non-qe pin\n", __func__); - gpiod_put(gpiod); + dev_dbg(dev, "%s: tried to get a non-qe pin\n", __func__); err = -EINVAL; goto err0; } return qe_pin; err0: kfree(qe_pin); - pr_debug("%s failed with status %d\n", __func__, err); + dev_dbg(dev, "%s failed with status %d\n", __func__, err); return ERR_PTR(err); } EXPORT_SYMBOL(qe_pin_request); @@ -220,7 +218,6 @@ EXPORT_SYMBOL(qe_pin_request); */ void qe_pin_free(struct qe_pin *qe_pin) { - gpiod_put(qe_pin->gpiod); kfree(qe_pin); } EXPORT_SYMBOL(qe_pin_free); diff --git a/drivers/usb/host/fhci-hcd.c b/drivers/usb/host/fhci-hcd.c index 95a44462bed0..1f666804fa91 100644 --- a/drivers/usb/host/fhci-hcd.c +++ b/drivers/usb/host/fhci-hcd.c @@ -651,7 +651,7 @@ static int of_fhci_probe(struct platform_device *ofdev) } for (j = 0; j < NUM_PINS; j++) { - fhci->pins[j] = qe_pin_request(node, j); + fhci->pins[j] = qe_pin_request(dev, j); if (IS_ERR(fhci->pins[j])) { ret = PTR_ERR(fhci->pins[j]); dev_err(dev, "can't get pin %d: %d\n", j, ret); diff --git a/include/soc/fsl/qe/qe.h b/include/soc/fsl/qe/qe.h index b02e9fe69146..eb5079904cc8 100644 --- a/include/soc/fsl/qe/qe.h +++ b/include/soc/fsl/qe/qe.h @@ -172,14 +172,15 @@ static inline int par_io_data_set(u8 port, u8 pin, u8 val) { return -ENOSYS; } /* * Pin multiplexing functions. */ +struct device; struct qe_pin; #ifdef CONFIG_QE_GPIO -extern struct qe_pin *qe_pin_request(struct device_node *np, int index); +extern struct qe_pin *qe_pin_request(struct device *dev, int index); extern void qe_pin_free(struct qe_pin *qe_pin); extern void qe_pin_set_gpio(struct qe_pin *qe_pin); extern void qe_pin_set_dedicated(struct qe_pin *pin); #else -static inline struct qe_pin *qe_pin_request(struct device_node *np, int index) +static inline struct qe_pin *qe_pin_request(struct device *dev, int index) { return ERR_PTR(-ENOSYS); }
Commit 84582f9ed090 ("soc: fsl: qe: Avoid using gpio_to_desc()") changed qe_pin_request() to request and hold GPIO corresponding to a given pin. Unfortunately this does not work, as fhci-hcd requests these GPIOs first, befor calling qe_pin_request() (see drivers/usb/host/fhci-hcd.c::of_fhci_probe()). To fix it change qe_pin_request() to request GPIOs non-exclusively, and free them once the code determines GPIO controller and offset for each GPIO/pin. Also reaching deep into gpiolib implementation is not the best idea. We should either export gpio_chip_hwgpio() or keep converting to the global gpio numbers space until we fix the driver to implement proper pin control. Fixes: 84582f9ed090 ("soc: fsl: qe: Avoid using gpio_to_desc()") Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> --- v2: - rebased on top of soc/driver. This will conflict with c9eb6e546a23 soc: fsl: qe: Switch to use fwnode instead of of_node found in next, the resolution is trivial: accept fwnode_device_is_compatible() line found in next. - fixed leak of gpiod when gc is not found - dropped Linus' reviewed-by as the patch changed drivers/soc/fsl/qe/gpio.c | 51 +++++++++++++++++-------------------- drivers/usb/host/fhci-hcd.c | 2 +- include/soc/fsl/qe/qe.h | 5 ++-- 3 files changed, 28 insertions(+), 30 deletions(-)