Re: [PATCH 1/3 v4] spi: s3c64xx: fix broken "cs_gpios" usage in the driver
From: Javier Martinez Canillas <hidden>
Date: 2014-06-12 14:00:19
Hello Naveen, On 06/12/2014 03:13 PM, Naveen Krishna Chatradhi wrote:
Since, (3146bee spi: s3c64xx: Added provision for dedicated cs pin)
spi-s3c64xx.c driver expects
1. chip select gpios from "cs-gpio"(singular) under the
"controller-data" node of the client/slave device of the SPI.
2. "cs-gpio"(singular) entry to be present in the SPI device node.
Eg of current broken usage:
&spi_1 {
cs-gpio <>; /* this entry is checked during probe */
...
slave_node {
controller-data {
cs-gpio <&gpioa2 5 0>;
/* This field is parsed during .setup() */
}
};
};
The following dts files which were using this driver. But,
din't have the "cs-gpio" entry under SPI node.
-- arch/arm/boot/dts/exynos4210-smdkv310.dts
-- arch/arm/boot/dts/exynos4412-trats2.dts
-- arch/arm/boot/dts/exynos5250-smdk5250.dts
Also, the SPI core and many drivers moved on to using "cs-gpios"
from SPI node and removed the gpio handling code from drivers
(including spi-s3c64xx.c).
Hence, spi-s3c64xx.c is broken since "Jun 21 11:26:12 2013" and
considering the time with no compliants about the breakage.
We are assuming it is safe to remove the "cs-gpio"(singular) usage
from device tree binding of spi-samsung.txt and makes appropriate
changes in the driver to use "cs-gpios"(plural) from
SPI device node.
Signed-off-by: Naveen Krishna Chatradhi <redacted>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Javier Martinez Canillas <redacted>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Tomasz Figa <redacted>
---Usually when you send a new version of a series is good to keep a history of the patch-set so reviewers don't have to look at the previous threads in order to see what changed from version to version. Anything that is between "---" and the actual diff is not part of a commit and tools like git am omits that part so that's were you usually describe the history.
quoted hunk
.../devicetree/bindings/spi/spi-samsung.txt | 8 ++-- drivers/spi/spi-s3c64xx.c | 41 ++++++++------------ 2 files changed, 20 insertions(+), 29 deletions(-)diff --git a/Documentation/devicetree/bindings/spi/spi-samsung.txt b/Documentation/devicetree/bindings/spi/spi-samsung.txt index 86aa061..2d29dac 100644 --- a/Documentation/devicetree/bindings/spi/spi-samsung.txt +++ b/Documentation/devicetree/bindings/spi/spi-samsung.txt@@ -42,15 +42,13 @@ Optional Board Specific Properties: - num-cs: Specifies the number of chip select lines supported. If not specified, the default number of chip select lines is set to 1. +- cs-gpios: should specify GPIOs used for chipselects (see spi-bus.txt) + SPI Controller specific data in SPI slave nodes: - The spi slave nodes should provide the following information which is required by the spi controller. - - cs-gpio: A gpio specifier that specifies the gpio line used as - the slave select line by the spi controller. The format of the gpio - specifier depends on the gpio controller. - - samsung,spi-feedback-delay: The sampling phase shift to be applied on the miso line (to account for any lag in the miso line). The following are the valid values.@@ -85,6 +83,7 @@ Example: #size-cells = <0>; pinctrl-names = "default"; pinctrl-0 = <&spi0_bus>; + cs-gpios = <&gpa2 5 0>; w25q80bw at 0 { #address-cells = <1>;@@ -94,7 +93,6 @@ Example: spi-max-frequency = <10000>; controller-data { - cs-gpio = <&gpa2 5 1 0 3>; samsung,spi-feedback-delay = <0>; };diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index 75a5696..b888c66 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c@@ -197,7 +197,6 @@ struct s3c64xx_spi_driver_data { struct s3c64xx_spi_dma_data tx_dma; struct s3c64xx_spi_port_config *port_conf; unsigned int port_id; - bool cs_gpio; }; static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)@@ -776,17 +775,6 @@ static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata( return ERR_PTR(-ENOMEM); } - /* The CS line is asserted/deasserted by the gpio pin */ - if (sdd->cs_gpio) - cs->line = of_get_named_gpio(data_np, "cs-gpio", 0); - - if (!gpio_is_valid(cs->line)) { - dev_err(&spi->dev, "chip select gpio is not specified or invalid\n"); - kfree(cs); - of_node_put(data_np); - return ERR_PTR(-EINVAL); - } - of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay); cs->fb_delay = fb_delay; of_node_put(data_np);@@ -812,6 +800,10 @@ static int s3c64xx_spi_setup(struct spi_device *spi) spi->controller_data = cs; } + /* For the non-DT platforms derive chip selects from controller data */ + if (!spi->dev.of_node) + spi->cs_gpio = cs->line; + if (IS_ERR_OR_NULL(cs)) { dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select); return -ENODEV;@@ -819,17 +811,19 @@ static int s3c64xx_spi_setup(struct spi_device *spi) if (!spi_get_ctldata(spi)) { /* Request gpio only if cs line is asserted by gpio pins */ - if (sdd->cs_gpio) { - err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH, - dev_name(&spi->dev)); + if (gpio_is_valid(spi->cs_gpio)) { + err = gpio_request_one(spi->cs_gpio, + GPIOF_OUT_INIT_HIGH, + dev_name(&spi->dev)); if (err) { dev_err(&spi->dev, "Failed to get /CS gpio [%d]: %d\n", - cs->line, err); + spi->cs_gpio, err); goto err_gpio_req; } - - spi->cs_gpio = cs->line; + } else { + dev_err(&spi->dev, "chip select gpio is invalid\n"); + return -EINVAL; } spi_set_ctldata(spi, cs);@@ -884,7 +878,8 @@ setup_exit: /* setup() returns with device de-selected */ writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); - gpio_free(cs->line); + if (gpio_is_valid(spi->cs_gpio)) + gpio_free(spi->cs_gpio); spi_set_ctldata(spi, NULL); err_gpio_req:@@ -900,10 +895,12 @@ static void s3c64xx_spi_cleanup(struct spi_device *spi) struct s3c64xx_spi_driver_data *sdd; sdd = spi_master_get_devdata(spi->master); - if (spi->cs_gpio) { + if (gpio_is_valid(spi->cs_gpio)) { gpio_free(spi->cs_gpio); if (spi->dev.of_node) kfree(cs); + else + spi->cs_gpio = -ENOENT; } spi_set_ctldata(spi, NULL); }@@ -1075,11 +1072,7 @@ static int s3c64xx_spi_probe(struct platform_device *pdev) sdd->cntrlr_info = sci; sdd->pdev = pdev; sdd->sfr_start = mem_res->start; - sdd->cs_gpio = true; if (pdev->dev.of_node) { - if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL)) - sdd->cs_gpio = false; - ret = of_alias_get_id(pdev->dev.of_node, "spi"); if (ret < 0) { dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
Your changes look good to me now. Reviewed-by: Javier Martinez Canillas <redacted> Best regards, Javier