From: Richard Genoud <richard.genoud-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> To: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> Cc: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org>, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Subject: [PATCH 02/23] of_spi: add generic binding support to specify cs gpio Date: Tue, 14 Aug 2012 15:49:16 +0200 [thread overview] Message-ID: <1344952177-18385-3-git-send-email-richard.genoud@gmail.com> (raw) In-Reply-To: <1344952177-18385-1-git-send-email-richard.genoud-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> From: Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org> This will allow to use gpio for chip select with no modification in the driver binding When use the cs-gpios, the gpio number will be passed via the cs_gpio field and the number of chip select will automatically increased. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org> Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Cc: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org --- Documentation/devicetree/bindings/spi/spi-bus.txt | 6 ++ drivers/spi/spi.c | 55 +++++++++++++++++++- include/linux/spi/spi.h | 3 + 3 files changed, 61 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index e782add..c253379 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. +- cs-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 cs-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/spi/spi.c b/drivers/spi/spi.c index 84c2861..3fb5b6d 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -30,6 +30,7 @@ #include <linux/slab.h> #include <linux/mod_devicetable.h> #include <linux/spi/spi.h> +#include <linux/of_gpio.h> #include <linux/pm_runtime.h> #include <linux/export.h> #include <linux/sched.h> @@ -327,6 +328,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master) spi->dev.parent = &master->dev; spi->dev.bus = &spi_bus_type; spi->dev.release = spidev_release; + spi->cs_gpio = -EINVAL; device_initialize(&spi->dev); return spi; } @@ -344,15 +346,16 @@ 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; } @@ -376,6 +379,9 @@ int spi_add_device(struct spi_device *spi) goto done; } + if (master->cs_gpios) + spi->cs_gpio = master->cs_gpios[spi->chip_select]; + /* 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... @@ -946,6 +952,45 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) } EXPORT_SYMBOL_GPL(spi_alloc_master); +#ifdef CONFIG_OF +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, "cs-gpios"); + + if (nb < 1) + return 0; + + cs = devm_kzalloc(&master->dev, + sizeof(int) * (master->num_chipselect + nb), + GFP_KERNEL); + master->cs_gpios = cs; + + if (!master->cs_gpios) + return -ENOMEM; + + memset(cs, -EINVAL, master->num_chipselect); + master->num_chipselect += nb; + cs += master->num_chipselect; + + for (i = 0; i < nb; i++) + cs[i] = of_get_named_gpio(np, "cs-gpios", i); + + return 0; +} +#else +static int of_spi_register_master(struct spi_master *master) +{ + return 0; +} +#endif + /** * spi_register_master - register SPI master controller * @master: initialized master, originally from spi_alloc_master() @@ -977,6 +1022,10 @@ 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 fa702ae..f629189 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -90,6 +90,7 @@ struct spi_device { void *controller_state; void *controller_data; char modalias[SPI_NAME_SIZE]; + int cs_gpio; /* chip select gpio */ /* * likely need more hooks for more protocol options affecting how @@ -362,6 +363,8 @@ struct spi_master { int (*transfer_one_message)(struct spi_master *master, struct spi_message *mesg); int (*unprepare_transfer_hardware)(struct spi_master *master); + /* gpio chip select */ + int *cs_gpios; }; static inline void *spi_master_get_devdata(struct spi_master *master) -- 1.7.2.5 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
WARNING: multiple messages have this Message-ID (diff)
From: richard.genoud@gmail.com (Richard Genoud) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 02/23] of_spi: add generic binding support to specify cs gpio Date: Tue, 14 Aug 2012 15:49:16 +0200 [thread overview] Message-ID: <1344952177-18385-3-git-send-email-richard.genoud@gmail.com> (raw) In-Reply-To: <1344952177-18385-1-git-send-email-richard.genoud@gmail.com> From: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> This will allow to use gpio for chip select with no modification in the driver binding When use the cs-gpios, the gpio number will be passed via the cs_gpio field and the number of chip select will automatically increased. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Cc: devicetree-discuss at lists.ozlabs.org Cc: spi-devel-general at lists.sourceforge.net --- Documentation/devicetree/bindings/spi/spi-bus.txt | 6 ++ drivers/spi/spi.c | 55 +++++++++++++++++++- include/linux/spi/spi.h | 3 + 3 files changed, 61 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index e782add..c253379 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. +- cs-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 cs-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/spi/spi.c b/drivers/spi/spi.c index 84c2861..3fb5b6d 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -30,6 +30,7 @@ #include <linux/slab.h> #include <linux/mod_devicetable.h> #include <linux/spi/spi.h> +#include <linux/of_gpio.h> #include <linux/pm_runtime.h> #include <linux/export.h> #include <linux/sched.h> @@ -327,6 +328,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master) spi->dev.parent = &master->dev; spi->dev.bus = &spi_bus_type; spi->dev.release = spidev_release; + spi->cs_gpio = -EINVAL; device_initialize(&spi->dev); return spi; } @@ -344,15 +346,16 @@ 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; } @@ -376,6 +379,9 @@ int spi_add_device(struct spi_device *spi) goto done; } + if (master->cs_gpios) + spi->cs_gpio = master->cs_gpios[spi->chip_select]; + /* 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... @@ -946,6 +952,45 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) } EXPORT_SYMBOL_GPL(spi_alloc_master); +#ifdef CONFIG_OF +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, "cs-gpios"); + + if (nb < 1) + return 0; + + cs = devm_kzalloc(&master->dev, + sizeof(int) * (master->num_chipselect + nb), + GFP_KERNEL); + master->cs_gpios = cs; + + if (!master->cs_gpios) + return -ENOMEM; + + memset(cs, -EINVAL, master->num_chipselect); + master->num_chipselect += nb; + cs += master->num_chipselect; + + for (i = 0; i < nb; i++) + cs[i] = of_get_named_gpio(np, "cs-gpios", i); + + return 0; +} +#else +static int of_spi_register_master(struct spi_master *master) +{ + return 0; +} +#endif + /** * spi_register_master - register SPI master controller * @master: initialized master, originally from spi_alloc_master() @@ -977,6 +1022,10 @@ 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@least one chipselect */ diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index fa702ae..f629189 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -90,6 +90,7 @@ struct spi_device { void *controller_state; void *controller_data; char modalias[SPI_NAME_SIZE]; + int cs_gpio; /* chip select gpio */ /* * likely need more hooks for more protocol options affecting how @@ -362,6 +363,8 @@ struct spi_master { int (*transfer_one_message)(struct spi_master *master, struct spi_message *mesg); int (*unprepare_transfer_hardware)(struct spi_master *master); + /* gpio chip select */ + int *cs_gpios; }; static inline void *spi_master_get_devdata(struct spi_master *master) -- 1.7.2.5
next prev parent reply other threads:[~2012-08-14 13:49 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-08-14 13:49 [PATCH 00/23] work in progress: SPI controller w/DMA SAM9X5 Richard Genoud 2012-08-14 13:49 ` [PATCH 01/23] of: add dma-mask binding Richard Genoud [not found] ` <1344952177-18385-1-git-send-email-richard.genoud-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2012-08-14 13:49 ` Richard Genoud [this message] 2012-08-14 13:49 ` [PATCH 02/23] of_spi: add generic binding support to specify cs gpio Richard Genoud 2012-08-14 13:49 ` [PATCH 08/23] spi/atmel: add DT support Richard Genoud 2012-08-14 13:49 ` Richard Genoud 2012-08-14 13:49 ` [PATCH 03/23] spi/atmel_spi: trivial: change some comments Richard Genoud 2012-08-14 13:49 ` [PATCH 04/23] spi/atmel_spi: add physical base address Richard Genoud 2012-08-14 13:49 ` [PATCH 05/23] spi/atmel_spi: call unmapping on transfers buffers Richard Genoud 2012-08-14 13:49 ` [PATCH 06/23] spi/atmel_spi: status information passed through controller data Richard Genoud 2012-08-14 13:49 ` [PATCH 07/23] spi/atmel_spi: add flag to controller data for lock operations Richard Genoud 2012-08-14 13:49 ` [PATCH 09/23] spi/atmel_spi: add dmaengine support Richard Genoud 2012-08-14 13:49 ` [PATCH 10/23] spi-atmel: update with dmaengine interface Richard Genoud 2012-08-14 13:49 ` [PATCH 11/23] spi-atmel: fix __init/__devinit sections mismatch Richard Genoud 2012-08-14 13:49 ` [PATCH 12/23] spi-atmel: Fix spi-atmel driver to adapt to slave_config changes Richard Genoud 2012-08-14 13:49 ` [PATCH 13/23] AT91 DMA OF support Richard Genoud 2012-08-14 14:47 ` Nicolas Ferre 2012-08-14 13:49 ` [PATCH 14/23] add at91sam9x5 Kconfig ARCH/SOC link Richard Genoud 2012-08-14 13:49 ` [PATCH 15/23] spi-atmel: add DMA OF support Richard Genoud 2012-08-14 13:49 ` [PATCH 16/23] [BUG] SPI: array out of bound => no CS Richard Genoud 2012-08-14 13:49 ` [PATCH 17/23] [BUG] atmel-spi && DMA: OOPS if buffer > 4400 bytes Richard Genoud 2012-08-14 13:49 ` [PATCH 18/23] sam9x5: declare SPI clocks Richard Genoud 2012-08-14 13:49 ` [PATCH 19/23] spi-atmel: add sam9x5 SPI in device tree Richard Genoud 2012-08-14 13:49 ` [PATCH 20/23] spi-atmel: add dma support in sam9x5 " Richard Genoud 2012-08-14 13:49 ` [PATCH 21/23] spi-atmel OF: complete documentation Richard Genoud 2012-08-14 13:49 ` [PATCH 22/23] spi-atmel: complete DMA slave OF documentation Richard Genoud 2012-08-14 13:49 ` [PATCH 23/23] sam9x5ek DTS: enable SPI dataflash Richard Genoud 2012-08-14 14:16 ` [PATCH 00/23] work in progress: SPI controller w/DMA SAM9X5 Richard Genoud 2012-08-14 15:29 ` Nicolas Ferre 2012-08-14 17:44 ` Jean-Christophe PLAGNIOL-VILLARD 2012-08-14 17:48 ` Nicolas Ferre 2012-08-16 7:07 ` Richard Genoud
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1344952177-18385-3-git-send-email-richard.genoud@gmail.com \ --to=richard.genoud-re5jqeeqqe8avxtiumwx3w@public.gmane.org \ --cc=devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org \ --cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \ --cc=nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org \ --cc=plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org \ --cc=spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.