From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Christophe PLAGNIOL-VILLARD Subject: Re: [PATCH 2/3] of_spi: add generic binding support to specify ncs gpio Date: Tue, 14 Feb 2012 05:24:19 +0100 Message-ID: <20120214042419.GG3378@game.jcrosoft.org> References: <1328804077-6121-1-git-send-email-plagnioj@jcrosoft.com> <1328804077-6121-2-git-send-email-plagnioj@jcrosoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: spi-devel-general@lists.sourceforge.net, devicetree-discuss@lists.ozlabs.org To: linux-arm-kernel@lists.infradead.org Return-path: Content-Disposition: inline In-Reply-To: <1328804077-6121-2-git-send-email-plagnioj@jcrosoft.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-spi.vger.kernel.org Hi Grant, ping Best Regards, J. On 17:14 Thu 09 Feb , Jean-Christophe PLAGNIOL-VILLARD wrote: > This will allow to use gpio for chip select with no modification in the > driver binding > > When use the ncs-gpios, the gpio number will be passed via the controller_data > and the number of chip select will automatically increased. > > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD > Cc: devicetree-discuss@lists.ozlabs.org > Cc: spi-devel-general@lists.sourceforge.net > --- > Documentation/devicetree/bindings/spi/spi-bus.txt | 6 +++ > drivers/of/of_spi.c | 27 ++++++++--- > drivers/spi/spi.c | 51 +++++++++++++++++++- > include/linux/spi/spi.h | 5 ++ > 4 files changed, 78 insertions(+), 11 deletions(-) > > diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt > index e782add..5a24729 100644 > --- a/Documentation/devicetree/bindings/spi/spi-bus.txt > +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt > @@ -12,6 +12,7 @@ The SPI master node requires the following properties: > - #size-cells - should be zero. > - compatible - name of SPI bus controller following generic names > recommended practice. > +- ncs-gpios - (optional) gpios chip select. > No other properties are required in the SPI bus node. It is assumed > that a driver for an SPI bus device will understand that it is an SPI bus. > However, the binding does not attempt to define the specific method for > @@ -21,6 +22,8 @@ assumption that board specific platform code will be used to manage > chip selects. Individual drivers can define additional properties to > support describing the chip select layout. > > +If ncs-gpios is used the number of chip select will automatically increased. > + > SPI slave nodes must be children of the SPI master node and can > contain the following properties. > - reg - (required) chip select address of device. > @@ -34,6 +37,9 @@ contain the following properties. > - spi-cs-high - (optional) Empty property indicating device requires > chip select active high > > +If a gpio chipselect is used for the SPI slave the gpio number will be passed > +via the controller_data > + > SPI example for an MPC5200 SPI bus: > spi@f00 { > #address-cells = <1>; > diff --git a/drivers/of/of_spi.c b/drivers/of/of_spi.c > index 6dbc074..0d41407 100644 > --- a/drivers/of/of_spi.c > +++ b/drivers/of/of_spi.c > @@ -12,6 +12,7 @@ > #include > #include > #include > +#include > > /** > * of_register_spi_devices - Register child devices onto the SPI bus > @@ -27,6 +28,7 @@ void of_register_spi_devices(struct spi_master *master) > const __be32 *prop; > int rc; > int len; > + int ncs_pin; > > if (!master->dev.of_node) > return; > @@ -50,15 +52,24 @@ void of_register_spi_devices(struct spi_master *master) > continue; > } > > - /* Device address */ > - prop = of_get_property(nc, "reg", &len); > - if (!prop || len < sizeof(*prop)) { > - dev_err(&master->dev, "%s has no 'reg' property\n", > - nc->full_name); > - spi_dev_put(spi); > - continue; > + /* ncs gpio */ > + ncs_pin = of_get_named_gpio(nc, "ncs-gpio", 0); > + > + if (gpio_is_valid(ncs_pin)) { > + spi->controller_data = (void *)ncs_pin; > + spi->chip_select = master->num_chipselect; > + master->num_chipselect++; > + } else { > + /* Device address */ > + prop = of_get_property(nc, "reg", &len); > + if (!prop || len < sizeof(*prop)) { > + dev_err(&master->dev, "%s has no 'reg' property\n", > + nc->full_name); > + spi_dev_put(spi); > + continue; > + } > + spi->chip_select = be32_to_cpup(prop); > } > - spi->chip_select = be32_to_cpup(prop); > > /* Mode (clock phase/polarity/etc.) */ > if (of_find_property(nc, "spi-cpha", NULL)) > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > index e2f4ca0..1f5ffa6 100644 > --- a/drivers/spi/spi.c > +++ b/drivers/spi/spi.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > #include > #include > > @@ -339,15 +340,16 @@ EXPORT_SYMBOL_GPL(spi_alloc_device); > int spi_add_device(struct spi_device *spi) > { > static DEFINE_MUTEX(spi_add_lock); > - struct device *dev = spi->master->dev.parent; > + struct spi_master *master = spi->master; > + struct device *dev = master->dev.parent; > struct device *d; > int status; > > /* Chipselects are numbered 0..max; validate. */ > - if (spi->chip_select >= spi->master->num_chipselect) { > + if (spi->chip_select >= master->num_chipselect) { > dev_err(dev, "cs%d >= max %d\n", > spi->chip_select, > - spi->master->num_chipselect); > + master->num_chipselect); > return -EINVAL; > } > > @@ -371,6 +373,13 @@ int spi_add_device(struct spi_device *spi) > goto done; > } > > + if (master->num_gpio_chipselect && > + spi->chip_select >= master->first_gpio_chipselect) { > + int num = spi->chip_select = master->first_gpio_chipselect; > + > + spi->controller_data = (void*)master->chipselect_gpios[num]; > + } > + > /* Drivers may modify this initial i/o setup, but will > * normally rely on the device being setup. Devices > * using SPI_CS_HIGH can't coexist well otherwise... > @@ -562,6 +571,38 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) > } > EXPORT_SYMBOL_GPL(spi_alloc_master); > > +static int of_spi_register_master(struct spi_master *master) > +{ > + int nb, i; > + int *cs; > + struct device_node *np = master->dev.of_node; > + > + if (!np) > + return 0; > + > + nb = of_gpio_named_count(np, "ncs-gpios"); > + > + if (nb < 1) > + return 0; > + > + master->chipselect_gpios = kzalloc(sizeof(int) * nb, GFP_KERNEL); > + > + if (!master->chipselect_gpios) > + return -ENOMEM; > + > + master->first_gpio_chipselect = master->num_chipselect; > + master->num_chipselect += nb; > + master->num_gpio_chipselect = nb; > + > + for (i = 0; i < nb; i++) { > + cs = &master->chipselect_gpios[i]; > + > + *cs = of_get_named_gpio(np, "ncs-gpios", i); > + } > + > + return 0; > +} > + > /** > * spi_register_master - register SPI master controller > * @master: initialized master, originally from spi_alloc_master() > @@ -593,6 +634,10 @@ int spi_register_master(struct spi_master *master) > if (!dev) > return -ENODEV; > > + status = of_spi_register_master(master); > + if (status) > + return status; > + > /* even if it's just one always-selected device, there must > * be at least one chipselect > */ > diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h > index 176fce9..d21c267 100644 > --- a/include/linux/spi/spi.h > +++ b/include/linux/spi/spi.h > @@ -318,6 +318,11 @@ struct spi_master { > > /* called on release() to free memory provided by spi_master */ > void (*cleanup)(struct spi_device *spi); > + > + /* gpio chip select */ > + int *chipselect_gpios; > + int first_gpio_chipselect; > + int num_gpio_chipselect; > }; > > static inline void *spi_master_get_devdata(struct spi_master *master) > -- > 1.7.7 From mboxrd@z Thu Jan 1 00:00:00 1970 From: plagnioj@jcrosoft.com (Jean-Christophe PLAGNIOL-VILLARD) Date: Tue, 14 Feb 2012 05:24:19 +0100 Subject: [PATCH 2/3] of_spi: add generic binding support to specify ncs gpio In-Reply-To: <1328804077-6121-2-git-send-email-plagnioj@jcrosoft.com> References: <1328804077-6121-1-git-send-email-plagnioj@jcrosoft.com> <1328804077-6121-2-git-send-email-plagnioj@jcrosoft.com> Message-ID: <20120214042419.GG3378@game.jcrosoft.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Grant, ping Best Regards, J. On 17:14 Thu 09 Feb , Jean-Christophe PLAGNIOL-VILLARD wrote: > This will allow to use gpio for chip select with no modification in the > driver binding > > When use the ncs-gpios, the gpio number will be passed via the controller_data > and the number of chip select will automatically increased. > > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD > Cc: devicetree-discuss at lists.ozlabs.org > Cc: spi-devel-general at lists.sourceforge.net > --- > Documentation/devicetree/bindings/spi/spi-bus.txt | 6 +++ > drivers/of/of_spi.c | 27 ++++++++--- > drivers/spi/spi.c | 51 +++++++++++++++++++- > include/linux/spi/spi.h | 5 ++ > 4 files changed, 78 insertions(+), 11 deletions(-) > > diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt > index e782add..5a24729 100644 > --- a/Documentation/devicetree/bindings/spi/spi-bus.txt > +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt > @@ -12,6 +12,7 @@ The SPI master node requires the following properties: > - #size-cells - should be zero. > - compatible - name of SPI bus controller following generic names > recommended practice. > +- ncs-gpios - (optional) gpios chip select. > No other properties are required in the SPI bus node. It is assumed > that a driver for an SPI bus device will understand that it is an SPI bus. > However, the binding does not attempt to define the specific method for > @@ -21,6 +22,8 @@ assumption that board specific platform code will be used to manage > chip selects. Individual drivers can define additional properties to > support describing the chip select layout. > > +If ncs-gpios is used the number of chip select will automatically increased. > + > SPI slave nodes must be children of the SPI master node and can > contain the following properties. > - reg - (required) chip select address of device. > @@ -34,6 +37,9 @@ contain the following properties. > - spi-cs-high - (optional) Empty property indicating device requires > chip select active high > > +If a gpio chipselect is used for the SPI slave the gpio number will be passed > +via the controller_data > + > SPI example for an MPC5200 SPI bus: > spi at f00 { > #address-cells = <1>; > diff --git a/drivers/of/of_spi.c b/drivers/of/of_spi.c > index 6dbc074..0d41407 100644 > --- a/drivers/of/of_spi.c > +++ b/drivers/of/of_spi.c > @@ -12,6 +12,7 @@ > #include > #include > #include > +#include > > /** > * of_register_spi_devices - Register child devices onto the SPI bus > @@ -27,6 +28,7 @@ void of_register_spi_devices(struct spi_master *master) > const __be32 *prop; > int rc; > int len; > + int ncs_pin; > > if (!master->dev.of_node) > return; > @@ -50,15 +52,24 @@ void of_register_spi_devices(struct spi_master *master) > continue; > } > > - /* Device address */ > - prop = of_get_property(nc, "reg", &len); > - if (!prop || len < sizeof(*prop)) { > - dev_err(&master->dev, "%s has no 'reg' property\n", > - nc->full_name); > - spi_dev_put(spi); > - continue; > + /* ncs gpio */ > + ncs_pin = of_get_named_gpio(nc, "ncs-gpio", 0); > + > + if (gpio_is_valid(ncs_pin)) { > + spi->controller_data = (void *)ncs_pin; > + spi->chip_select = master->num_chipselect; > + master->num_chipselect++; > + } else { > + /* Device address */ > + prop = of_get_property(nc, "reg", &len); > + if (!prop || len < sizeof(*prop)) { > + dev_err(&master->dev, "%s has no 'reg' property\n", > + nc->full_name); > + spi_dev_put(spi); > + continue; > + } > + spi->chip_select = be32_to_cpup(prop); > } > - spi->chip_select = be32_to_cpup(prop); > > /* Mode (clock phase/polarity/etc.) */ > if (of_find_property(nc, "spi-cpha", NULL)) > diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c > index e2f4ca0..1f5ffa6 100644 > --- a/drivers/spi/spi.c > +++ b/drivers/spi/spi.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > #include > #include > > @@ -339,15 +340,16 @@ EXPORT_SYMBOL_GPL(spi_alloc_device); > int spi_add_device(struct spi_device *spi) > { > static DEFINE_MUTEX(spi_add_lock); > - struct device *dev = spi->master->dev.parent; > + struct spi_master *master = spi->master; > + struct device *dev = master->dev.parent; > struct device *d; > int status; > > /* Chipselects are numbered 0..max; validate. */ > - if (spi->chip_select >= spi->master->num_chipselect) { > + if (spi->chip_select >= master->num_chipselect) { > dev_err(dev, "cs%d >= max %d\n", > spi->chip_select, > - spi->master->num_chipselect); > + master->num_chipselect); > return -EINVAL; > } > > @@ -371,6 +373,13 @@ int spi_add_device(struct spi_device *spi) > goto done; > } > > + if (master->num_gpio_chipselect && > + spi->chip_select >= master->first_gpio_chipselect) { > + int num = spi->chip_select = master->first_gpio_chipselect; > + > + spi->controller_data = (void*)master->chipselect_gpios[num]; > + } > + > /* Drivers may modify this initial i/o setup, but will > * normally rely on the device being setup. Devices > * using SPI_CS_HIGH can't coexist well otherwise... > @@ -562,6 +571,38 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) > } > EXPORT_SYMBOL_GPL(spi_alloc_master); > > +static int of_spi_register_master(struct spi_master *master) > +{ > + int nb, i; > + int *cs; > + struct device_node *np = master->dev.of_node; > + > + if (!np) > + return 0; > + > + nb = of_gpio_named_count(np, "ncs-gpios"); > + > + if (nb < 1) > + return 0; > + > + master->chipselect_gpios = kzalloc(sizeof(int) * nb, GFP_KERNEL); > + > + if (!master->chipselect_gpios) > + return -ENOMEM; > + > + master->first_gpio_chipselect = master->num_chipselect; > + master->num_chipselect += nb; > + master->num_gpio_chipselect = nb; > + > + for (i = 0; i < nb; i++) { > + cs = &master->chipselect_gpios[i]; > + > + *cs = of_get_named_gpio(np, "ncs-gpios", i); > + } > + > + return 0; > +} > + > /** > * spi_register_master - register SPI master controller > * @master: initialized master, originally from spi_alloc_master() > @@ -593,6 +634,10 @@ int spi_register_master(struct spi_master *master) > if (!dev) > return -ENODEV; > > + status = of_spi_register_master(master); > + if (status) > + return status; > + > /* even if it's just one always-selected device, there must > * be at least one chipselect > */ > diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h > index 176fce9..d21c267 100644 > --- a/include/linux/spi/spi.h > +++ b/include/linux/spi/spi.h > @@ -318,6 +318,11 @@ struct spi_master { > > /* called on release() to free memory provided by spi_master */ > void (*cleanup)(struct spi_device *spi); > + > + /* gpio chip select */ > + int *chipselect_gpios; > + int first_gpio_chipselect; > + int num_gpio_chipselect; > }; > > static inline void *spi_master_get_devdata(struct spi_master *master) > -- > 1.7.7