| Message ID | Y2nKIbKxHAMimxII@google.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | soc: fsl: qe: request pins non-exclusively | expand |
On Tue, Nov 8, 2022 at 4:16 AM Dmitry Torokhov <dmitry.torokhov@gmail.com> 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. > > 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> Wow! Thanks for fixing this! Reviewed-by: Linus Walleij <linus.walleij@linaro.org> I just sent that patch into the SoC patch tracker (soc@kernel.org) with a not to apply it directly, I suggest you do the same (or ask me to sign it off and send it). Yours, Linus Walleij
On Tue, Nov 08, 2022 at 11:50:07AM +0100, Linus Walleij wrote: > On Tue, Nov 8, 2022 at 4:16 AM Dmitry Torokhov > <dmitry.torokhov@gmail.com> 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. > > > > 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> > > Wow! Thanks for fixing this! > > Reviewed-by: Linus Walleij <linus.walleij@linaro.org> > > I just sent that patch into the SoC patch tracker (soc@kernel.org) > with a not to apply it directly, I suggest you do the same (or ask me > to sign it off and send it). It depends on the patch in my tree, which is in your tree as well. I guess you need to take or wait for v6.2-rc1.
On November 8, 2022 2:50:07 AM PST, Linus Walleij <linus.walleij@linaro.org> wrote: >On Tue, Nov 8, 2022 at 4:16 AM Dmitry Torokhov ><dmitry.torokhov@gmail.com> 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. >> >> 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> > >Wow! Thanks for fixing this! > >Reviewed-by: Linus Walleij <linus.walleij@linaro.org> > >I just sent that patch into the SoC patch tracker (soc@kernel.org) >with a not to apply it directly, I suggest you do the same (or ask me >to sign it off and send it). I am not really plugged into soc patch/workflow so if you could do that that would be wonderful. Thanks!
diff --git a/drivers/soc/fsl/qe/gpio.c b/drivers/soc/fsl/qe/gpio.c index 0ee887f89deb..5bb71a2b5b7a 100644 --- a/drivers/soc/fsl/qe/gpio.c +++ b/drivers/soc/fsl/qe/gpio.c @@ -13,7 +13,7 @@ #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> @@ -21,13 +21,6 @@ #include <linux/property.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; @@ -149,20 +142,19 @@ 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; @@ -171,40 +163,46 @@ struct qe_pin *qe_pin_request(struct device_node *np, int index) 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 was 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); 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); - - if (!fwnode_device_is_compatible(gc->fwnode, "fsl,mpc8323-qe-pario-bank")) { - pr_debug("%s: tried to get a non-qe pin\n", __func__); - gpiod_put(gpiod); + } else if (!fwnode_device_is_compatible(gc->fwnode, + "fsl,mpc8323-qe-pario-bank")) { + dev_dbg(dev, "%s: tried to get a non-qe pin\n", __func__); err = -EINVAL; - goto err0; + } else { + 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 = desc_to_gpio(gpiod) - gc->base; } - return qe_pin; + + /* We no longer need this descriptor */ + gpiod_put(gpiod); + + if (!err) + return qe_pin; + err0: kfree(qe_pin); pr_debug("%s failed with status %d\n", __func__, err); @@ -222,7 +220,6 @@ 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> --- Compiled only, not tested on hardware. drivers/soc/fsl/qe/gpio.c | 71 ++++++++++++++++++------------------- drivers/usb/host/fhci-hcd.c | 2 +- include/soc/fsl/qe/qe.h | 5 +-- 3 files changed, 38 insertions(+), 40 deletions(-)