| Message ID | 20161108174852.14311-1-nicolas.ferre@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 08/11/2016 at 18:48:52 +0100, Nicolas Ferre wrote : > Use the managed gpio CS pin request so that we avoid having trouble > in the cleanup code. > In fact, if module was configured with DT, cleanup code released > invalid pin. Since resource wasn't freed, module cannot be reinserted. > > This require to extract the gpio request call from the "setup" function > and call it in the appropriate probe function. > > Reported-by: Alexander Morozov <linux@meltdown.ru> > Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> I think that's fine but I still have that item on my todo list (discussion in july 2014 with Mark): --- >> Mark: maybe it would make sense to do devm_gpio_request_one() in >> of_spi_register_master(), after of_get_named_gpio. > You need to transition all the drivers doing things manually but yes. > As I keep saying all the GPIO handling needs to be completely > refactored. --- > --- > v2: fix devm_gpio_request location: the setup code for device was not proper > location. Move it to the probe function and add needed DT routines to > handle all CS gpio specified. > > drivers/spi/spi-atmel.c | 50 ++++++++++++++++++++++++++++++++++++++----------- > 1 file changed, 39 insertions(+), 11 deletions(-) > > diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c > index 32683a13dd60..a60925614480 100644 > --- a/drivers/spi/spi-atmel.c > +++ b/drivers/spi/spi-atmel.c > @@ -24,6 +24,7 @@ > > #include <linux/io.h> > #include <linux/gpio.h> > +#include <linux/of_gpio.h> > #include <linux/pinctrl/consumer.h> > #include <linux/pm_runtime.h> > > @@ -1204,7 +1205,6 @@ static int atmel_spi_setup(struct spi_device *spi) > u32 csr; > unsigned int bits = spi->bits_per_word; > unsigned int npcs_pin; > - int ret; > > as = spi_master_get_devdata(spi->master); > > @@ -1247,16 +1247,9 @@ static int atmel_spi_setup(struct spi_device *spi) > if (!asd) > return -ENOMEM; > > - if (as->use_cs_gpios) { > - ret = gpio_request(npcs_pin, dev_name(&spi->dev)); > - if (ret) { > - kfree(asd); > - return ret; > - } > - > + if (as->use_cs_gpios) > gpio_direction_output(npcs_pin, > !(spi->mode & SPI_CS_HIGH)); > - } > > asd->npcs_pin = npcs_pin; > spi->controller_state = asd; > @@ -1471,13 +1464,11 @@ static int atmel_spi_transfer_one_message(struct spi_master *master, > static void atmel_spi_cleanup(struct spi_device *spi) > { > struct atmel_spi_device *asd = spi->controller_state; > - unsigned gpio = (unsigned long) spi->controller_data; > > if (!asd) > return; > > spi->controller_state = NULL; > - gpio_free(gpio); > kfree(asd); > } > > @@ -1499,6 +1490,39 @@ static void atmel_get_caps(struct atmel_spi *as) > } > > /*-------------------------------------------------------------------------*/ > +static int atmel_spi_gpio_cs(struct platform_device *pdev) > +{ > + struct spi_master *master = platform_get_drvdata(pdev); > + struct atmel_spi *as = spi_master_get_devdata(master); > + struct device_node *np = master->dev.of_node; > + int i; > + int ret = 0; > + int nb = 0; > + > + if (!as->use_cs_gpios) > + return 0; > + > + if (!np) > + return 0; > + > + nb = of_gpio_named_count(np, "cs-gpios"); > + for (i = 0; i < nb; i++) { > + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, > + "cs-gpios", i); > + > + if (cs_gpio == -EPROBE_DEFER) > + return cs_gpio; > + > + if (gpio_is_valid(cs_gpio)) { > + ret = devm_gpio_request(&pdev->dev, cs_gpio, > + dev_name(&pdev->dev)); > + if (ret) > + return ret; > + } > + } > + > + return 0; > +} > > static int atmel_spi_probe(struct platform_device *pdev) > { > @@ -1577,6 +1601,10 @@ static int atmel_spi_probe(struct platform_device *pdev) > master->num_chipselect = 4; > } > > + ret = atmel_spi_gpio_cs(pdev); > + if (ret) > + goto out_unmap_regs; > + > as->use_dma = false; > as->use_pdc = false; > if (as->caps.has_dma_support) { > -- > 2.9.0 >
Le 08/11/2016 à 18:49, Alexandre Belloni a écrit : > On 08/11/2016 at 18:48:52 +0100, Nicolas Ferre wrote : >> Use the managed gpio CS pin request so that we avoid having trouble >> in the cleanup code. >> In fact, if module was configured with DT, cleanup code released >> invalid pin. Since resource wasn't freed, module cannot be reinserted. >> >> This require to extract the gpio request call from the "setup" function >> and call it in the appropriate probe function. >> >> Reported-by: Alexander Morozov <linux@meltdown.ru> >> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> > > I think that's fine but I still have that item on my todo list > (discussion in july 2014 with Mark): > > --- >>> Mark: maybe it would make sense to do devm_gpio_request_one() in >>> of_spi_register_master(), after of_get_named_gpio. > >> You need to transition all the drivers doing things manually but yes. >> As I keep saying all the GPIO handling needs to be completely >> refactored. > --- Would make sense indeed as we are currently doing the same node scanning twice... But this patch actually fixes an issue with module unloading/re-loading and freeing of a wrong gpio. So I do think that we shouldn't hold its adoption while thinking about this enhancement... Regards, >> --- >> v2: fix devm_gpio_request location: the setup code for device was not proper >> location. Move it to the probe function and add needed DT routines to >> handle all CS gpio specified. >> >> drivers/spi/spi-atmel.c | 50 ++++++++++++++++++++++++++++++++++++++----------- >> 1 file changed, 39 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c >> index 32683a13dd60..a60925614480 100644 >> --- a/drivers/spi/spi-atmel.c >> +++ b/drivers/spi/spi-atmel.c >> @@ -24,6 +24,7 @@ >> >> #include <linux/io.h> >> #include <linux/gpio.h> >> +#include <linux/of_gpio.h> >> #include <linux/pinctrl/consumer.h> >> #include <linux/pm_runtime.h> >> >> @@ -1204,7 +1205,6 @@ static int atmel_spi_setup(struct spi_device *spi) >> u32 csr; >> unsigned int bits = spi->bits_per_word; >> unsigned int npcs_pin; >> - int ret; >> >> as = spi_master_get_devdata(spi->master); >> >> @@ -1247,16 +1247,9 @@ static int atmel_spi_setup(struct spi_device *spi) >> if (!asd) >> return -ENOMEM; >> >> - if (as->use_cs_gpios) { >> - ret = gpio_request(npcs_pin, dev_name(&spi->dev)); >> - if (ret) { >> - kfree(asd); >> - return ret; >> - } >> - >> + if (as->use_cs_gpios) >> gpio_direction_output(npcs_pin, >> !(spi->mode & SPI_CS_HIGH)); >> - } >> >> asd->npcs_pin = npcs_pin; >> spi->controller_state = asd; >> @@ -1471,13 +1464,11 @@ static int atmel_spi_transfer_one_message(struct spi_master *master, >> static void atmel_spi_cleanup(struct spi_device *spi) >> { >> struct atmel_spi_device *asd = spi->controller_state; >> - unsigned gpio = (unsigned long) spi->controller_data; >> >> if (!asd) >> return; >> >> spi->controller_state = NULL; >> - gpio_free(gpio); >> kfree(asd); >> } >> >> @@ -1499,6 +1490,39 @@ static void atmel_get_caps(struct atmel_spi *as) >> } >> >> /*-------------------------------------------------------------------------*/ >> +static int atmel_spi_gpio_cs(struct platform_device *pdev) >> +{ >> + struct spi_master *master = platform_get_drvdata(pdev); >> + struct atmel_spi *as = spi_master_get_devdata(master); >> + struct device_node *np = master->dev.of_node; >> + int i; >> + int ret = 0; >> + int nb = 0; >> + >> + if (!as->use_cs_gpios) >> + return 0; >> + >> + if (!np) >> + return 0; >> + >> + nb = of_gpio_named_count(np, "cs-gpios"); >> + for (i = 0; i < nb; i++) { >> + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, >> + "cs-gpios", i); >> + >> + if (cs_gpio == -EPROBE_DEFER) >> + return cs_gpio; >> + >> + if (gpio_is_valid(cs_gpio)) { >> + ret = devm_gpio_request(&pdev->dev, cs_gpio, >> + dev_name(&pdev->dev)); >> + if (ret) >> + return ret; >> + } >> + } >> + >> + return 0; >> +} >> >> static int atmel_spi_probe(struct platform_device *pdev) >> { >> @@ -1577,6 +1601,10 @@ static int atmel_spi_probe(struct platform_device *pdev) >> master->num_chipselect = 4; >> } >> >> + ret = atmel_spi_gpio_cs(pdev); >> + if (ret) >> + goto out_unmap_regs; >> + >> as->use_dma = false; >> as->use_pdc = false; >> if (as->caps.has_dma_support) { >> -- >> 2.9.0 >> >
On 09/11/2016 at 10:16:18 +0100, Nicolas Ferre wrote : > Le 08/11/2016 à 18:49, Alexandre Belloni a écrit : > > On 08/11/2016 at 18:48:52 +0100, Nicolas Ferre wrote : > >> Use the managed gpio CS pin request so that we avoid having trouble > >> in the cleanup code. > >> In fact, if module was configured with DT, cleanup code released > >> invalid pin. Since resource wasn't freed, module cannot be reinserted. > >> > >> This require to extract the gpio request call from the "setup" function > >> and call it in the appropriate probe function. > >> > >> Reported-by: Alexander Morozov <linux@meltdown.ru> > >> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> > > > > I think that's fine but I still have that item on my todo list > > (discussion in july 2014 with Mark): > > > > --- > >>> Mark: maybe it would make sense to do devm_gpio_request_one() in > >>> of_spi_register_master(), after of_get_named_gpio. > > > >> You need to transition all the drivers doing things manually but yes. > >> As I keep saying all the GPIO handling needs to be completely > >> refactored. > > --- > > Would make sense indeed as we are currently doing the same node scanning > twice... > > But this patch actually fixes an issue with module unloading/re-loading > and freeing of a wrong gpio. So I do think that we shouldn't hold its > adoption while thinking about this enhancement... > Yes, this patch is still useful as-is and fixes a bug. > Regards, > > >> --- > >> v2: fix devm_gpio_request location: the setup code for device was not proper > >> location. Move it to the probe function and add needed DT routines to > >> handle all CS gpio specified. > >> > >> drivers/spi/spi-atmel.c | 50 ++++++++++++++++++++++++++++++++++++++----------- > >> 1 file changed, 39 insertions(+), 11 deletions(-) > >> > >> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c > >> index 32683a13dd60..a60925614480 100644 > >> --- a/drivers/spi/spi-atmel.c > >> +++ b/drivers/spi/spi-atmel.c > >> @@ -24,6 +24,7 @@ > >> > >> #include <linux/io.h> > >> #include <linux/gpio.h> > >> +#include <linux/of_gpio.h> > >> #include <linux/pinctrl/consumer.h> > >> #include <linux/pm_runtime.h> > >> > >> @@ -1204,7 +1205,6 @@ static int atmel_spi_setup(struct spi_device *spi) > >> u32 csr; > >> unsigned int bits = spi->bits_per_word; > >> unsigned int npcs_pin; > >> - int ret; > >> > >> as = spi_master_get_devdata(spi->master); > >> > >> @@ -1247,16 +1247,9 @@ static int atmel_spi_setup(struct spi_device *spi) > >> if (!asd) > >> return -ENOMEM; > >> > >> - if (as->use_cs_gpios) { > >> - ret = gpio_request(npcs_pin, dev_name(&spi->dev)); > >> - if (ret) { > >> - kfree(asd); > >> - return ret; > >> - } > >> - > >> + if (as->use_cs_gpios) > >> gpio_direction_output(npcs_pin, > >> !(spi->mode & SPI_CS_HIGH)); > >> - } > >> > >> asd->npcs_pin = npcs_pin; > >> spi->controller_state = asd; > >> @@ -1471,13 +1464,11 @@ static int atmel_spi_transfer_one_message(struct spi_master *master, > >> static void atmel_spi_cleanup(struct spi_device *spi) > >> { > >> struct atmel_spi_device *asd = spi->controller_state; > >> - unsigned gpio = (unsigned long) spi->controller_data; > >> > >> if (!asd) > >> return; > >> > >> spi->controller_state = NULL; > >> - gpio_free(gpio); > >> kfree(asd); > >> } > >> > >> @@ -1499,6 +1490,39 @@ static void atmel_get_caps(struct atmel_spi *as) > >> } > >> > >> /*-------------------------------------------------------------------------*/ > >> +static int atmel_spi_gpio_cs(struct platform_device *pdev) > >> +{ > >> + struct spi_master *master = platform_get_drvdata(pdev); > >> + struct atmel_spi *as = spi_master_get_devdata(master); > >> + struct device_node *np = master->dev.of_node; > >> + int i; > >> + int ret = 0; > >> + int nb = 0; > >> + > >> + if (!as->use_cs_gpios) > >> + return 0; > >> + > >> + if (!np) > >> + return 0; > >> + > >> + nb = of_gpio_named_count(np, "cs-gpios"); > >> + for (i = 0; i < nb; i++) { > >> + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, > >> + "cs-gpios", i); > >> + > >> + if (cs_gpio == -EPROBE_DEFER) > >> + return cs_gpio; > >> + > >> + if (gpio_is_valid(cs_gpio)) { > >> + ret = devm_gpio_request(&pdev->dev, cs_gpio, > >> + dev_name(&pdev->dev)); > >> + if (ret) > >> + return ret; > >> + } > >> + } > >> + > >> + return 0; > >> +} > >> > >> static int atmel_spi_probe(struct platform_device *pdev) > >> { > >> @@ -1577,6 +1601,10 @@ static int atmel_spi_probe(struct platform_device *pdev) > >> master->num_chipselect = 4; > >> } > >> > >> + ret = atmel_spi_gpio_cs(pdev); > >> + if (ret) > >> + goto out_unmap_regs; > >> + > >> as->use_dma = false; > >> as->use_pdc = false; > >> if (as->caps.has_dma_support) { > >> -- > >> 2.9.0 > >> > > > > > -- > Nicolas Ferre
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 32683a13dd60..a60925614480 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -24,6 +24,7 @@ #include <linux/io.h> #include <linux/gpio.h> +#include <linux/of_gpio.h> #include <linux/pinctrl/consumer.h> #include <linux/pm_runtime.h> @@ -1204,7 +1205,6 @@ static int atmel_spi_setup(struct spi_device *spi) u32 csr; unsigned int bits = spi->bits_per_word; unsigned int npcs_pin; - int ret; as = spi_master_get_devdata(spi->master); @@ -1247,16 +1247,9 @@ static int atmel_spi_setup(struct spi_device *spi) if (!asd) return -ENOMEM; - if (as->use_cs_gpios) { - ret = gpio_request(npcs_pin, dev_name(&spi->dev)); - if (ret) { - kfree(asd); - return ret; - } - + if (as->use_cs_gpios) gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH)); - } asd->npcs_pin = npcs_pin; spi->controller_state = asd; @@ -1471,13 +1464,11 @@ static int atmel_spi_transfer_one_message(struct spi_master *master, static void atmel_spi_cleanup(struct spi_device *spi) { struct atmel_spi_device *asd = spi->controller_state; - unsigned gpio = (unsigned long) spi->controller_data; if (!asd) return; spi->controller_state = NULL; - gpio_free(gpio); kfree(asd); } @@ -1499,6 +1490,39 @@ static void atmel_get_caps(struct atmel_spi *as) } /*-------------------------------------------------------------------------*/ +static int atmel_spi_gpio_cs(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct atmel_spi *as = spi_master_get_devdata(master); + struct device_node *np = master->dev.of_node; + int i; + int ret = 0; + int nb = 0; + + if (!as->use_cs_gpios) + return 0; + + if (!np) + return 0; + + nb = of_gpio_named_count(np, "cs-gpios"); + for (i = 0; i < nb; i++) { + int cs_gpio = of_get_named_gpio(pdev->dev.of_node, + "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) + return cs_gpio; + + if (gpio_is_valid(cs_gpio)) { + ret = devm_gpio_request(&pdev->dev, cs_gpio, + dev_name(&pdev->dev)); + if (ret) + return ret; + } + } + + return 0; +} static int atmel_spi_probe(struct platform_device *pdev) { @@ -1577,6 +1601,10 @@ static int atmel_spi_probe(struct platform_device *pdev) master->num_chipselect = 4; } + ret = atmel_spi_gpio_cs(pdev); + if (ret) + goto out_unmap_regs; + as->use_dma = false; as->use_pdc = false; if (as->caps.has_dma_support) {
Use the managed gpio CS pin request so that we avoid having trouble in the cleanup code. In fact, if module was configured with DT, cleanup code released invalid pin. Since resource wasn't freed, module cannot be reinserted. This require to extract the gpio request call from the "setup" function and call it in the appropriate probe function. Reported-by: Alexander Morozov <linux@meltdown.ru> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> --- v2: fix devm_gpio_request location: the setup code for device was not proper location. Move it to the probe function and add needed DT routines to handle all CS gpio specified. drivers/spi/spi-atmel.c | 50 ++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 39 insertions(+), 11 deletions(-)