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spi: s3c64xx: add device tree support

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Add support for device based discovery.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Jaswinder Singh <jaswinder.singh@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This commit is contained in:
Thomas Abraham 2012-07-13 07:15:15 +09:00 committed by Kukjin Kim
parent 1c20c200ef
commit 2b90807549
2 changed files with 377 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

113
Documentation/devicetree/bindings/spi/spi-samsung.txt Normal file
View File

@ -0,0 +1,113 @@
* Samsung SPI Controller
The Samsung SPI controller is used to interface with various devices such as flash
and display controllers using the SPI communication interface.
Required SoC Specific Properties:
- compatible: should be one of the following.
- samsung,s3c2443-spi: for s3c2443, s3c2416 and s3c2450 platforms
- samsung,s3c6410-spi: for s3c6410 platforms
- samsung,s5p6440-spi: for s5p6440 and s5p6450 platforms
- samsung,s5pv210-spi: for s5pv210 and s5pc110 platforms
- samsung,exynos4210-spi: for exynos4 and exynos5 platforms
- reg: physical base address of the controller and length of memory mapped
region.
- interrupts: The interrupt number to the cpu. The interrupt specifier format
depends on the interrupt controller.
- tx-dma-channel: The dma channel specifier for tx operations. The format of
the dma specifier depends on the dma controller.
- rx-dma-channel: The dma channel specifier for rx operations. The format of
the dma specifier depends on the dma controller.
Required Board Specific Properties:
- #address-cells: should be 1.
- #size-cells: should be 0.
- gpios: The gpio specifier for clock, mosi and miso interface lines (in the
order specified). The format of the gpio specifier depends on the gpio
controller.
Optional Board Specific Properties:
- samsung,spi-src-clk: If the spi controller includes a internal clock mux to
select the clock source for the spi bus clock, this property can be used to
indicate the clock to be used for driving the spi bus clock. If not specified,
the clock number 0 is used as default.
- num-cs: Specifies the number of chip select lines supported. If
not specified, the default number of chip select lines is set to 1.
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.
- 0: No phase shift.
- 1: 90 degree phase shift sampling.
- 2: 180 degree phase shift sampling.
- 3: 270 degree phase shift sampling.
Aliases:
- All the SPI controller nodes should be represented in the aliases node using
the following format 'spi{n}' where n is a unique number for the alias.
Example:
- SoC Specific Portion:
spi_0: spi@12d20000 {
compatible = "samsung,exynos4210-spi";
reg = <0x12d20000 0x100>;
interrupts = <0 66 0>;
tx-dma-channel = <&pdma0 5>;
rx-dma-channel = <&pdma0 4>;
};
- Board Specific Portion:
spi_0: spi@12d20000 {
#address-cells = <1>;
#size-cells = <0>;
gpios = <&gpa2 4 2 3 0>,
<&gpa2 6 2 3 0>,
<&gpa2 7 2 3 0>;
w25q80bw@0 {
#address-cells = <1>;
#size-cells = <1>;
compatible = "w25x80";
reg = <0>;
spi-max-frequency = <10000>;
controller-data {
cs-gpio = <&gpa2 5 1 0 3>;
samsung,spi-feedback-delay = <0>;
};
partition@0 {
label = "U-Boot";
reg = <0x0 0x40000>;
read-only;
};
partition@40000 {
label = "Kernel";
reg = <0x40000 0xc0000>;
};
};
};

303
drivers/spi/spi-s3c64xx.c
View File

@ -28,6 +28,8 @@
#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <mach/dma.h>
#include <plat/s3c64xx-spi.h>
@ -137,6 +139,7 @@ struct s3c64xx_spi_dma_data {
unsigned ch;
enum dma_data_direction direction;
enum dma_ch dmach;
struct property *dma_prop;
};
/**
@ -201,6 +204,7 @@ struct s3c64xx_spi_driver_data {
struct samsung_dma_ops *ops;
struct s3c64xx_spi_port_config *port_conf;
unsigned int port_id;
unsigned long gpios[4];
};
static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
@ -326,7 +330,9 @@ static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
req.cap = DMA_SLAVE;
req.client = &s3c64xx_spi_dma_client;
req.dt_dmach_prop = sdd->rx_dma.dma_prop;
sdd->rx_dma.ch = sdd->ops->request(sdd->rx_dma.dmach, &req);
req.dt_dmach_prop = sdd->tx_dma.dma_prop;
sdd->tx_dma.ch = sdd->ops->request(sdd->tx_dma.dmach, &req);
return 1;
@ -819,6 +825,48 @@ static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
return 0;
}
static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
struct s3c64xx_spi_driver_data *sdd,
struct spi_device *spi)
{
struct s3c64xx_spi_csinfo *cs;
struct device_node *slave_np, *data_np;
u32 fb_delay = 0;
slave_np = spi->dev.of_node;
if (!slave_np) {
dev_err(&spi->dev, "device node not found\n");
return ERR_PTR(-EINVAL);
}
for_each_child_of_node(slave_np, data_np)
if (!strcmp(data_np->name, "controller-data"))
break;
if (!data_np) {
dev_err(&spi->dev, "child node 'controller-data' not found\n");
return ERR_PTR(-EINVAL);
}
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs) {
dev_err(&spi->dev, "could not allocate memory for controller"
" data\n");
return ERR_PTR(-ENOMEM);
}
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);
return ERR_PTR(-EINVAL);
}
of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
cs->fb_delay = fb_delay;
return cs;
}
/*
* Here we only check the validity of requested configuration
* and save the configuration in a local data-structure.
@ -832,9 +880,15 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
struct s3c64xx_spi_info *sci;
struct spi_message *msg;
unsigned long flags;
int err = 0;
int err;
if (cs == NULL) {
sdd = spi_master_get_devdata(spi->master);
if (!cs && spi->dev.of_node) {
cs = s3c64xx_get_slave_ctrldata(sdd, spi);
spi->controller_data = cs;
}
if (IS_ERR_OR_NULL(cs)) {
dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
return -ENODEV;
}
@ -844,12 +898,12 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
if (err) {
dev_err(&spi->dev, "request for slave select gpio "
"line [%d] failed\n", cs->line);
return -EBUSY;
err = -EBUSY;
goto err_gpio_req;
}
spi_set_ctldata(spi, cs);
}
sdd = spi_master_get_devdata(spi->master);
sci = sdd->cntrlr_info;
spin_lock_irqsave(&sdd->lock, flags);
@ -860,7 +914,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
dev_err(&spi->dev,
"setup: attempt while mssg in queue!\n");
spin_unlock_irqrestore(&sdd->lock, flags);
return -EBUSY;
err = -EBUSY;
goto err_msgq;
}
}
@ -903,19 +958,29 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
}
speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
if (spi->max_speed_hz >= speed)
if (spi->max_speed_hz >= speed) {
spi->max_speed_hz = speed;
else
} else {
err = -EINVAL;
goto setup_exit;
}
}
pm_runtime_put(&sdd->pdev->dev);
disable_cs(sdd, spi);
return 0;
setup_exit:
/* setup() returns with device de-selected */
disable_cs(sdd, spi);
err_msgq:
gpio_free(cs->line);
spi_set_ctldata(spi, NULL);
err_gpio_req:
kfree(cs);
return err;
}
@ -923,8 +988,11 @@ static void s3c64xx_spi_cleanup(struct spi_device *spi)
{
struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
if (cs)
if (cs) {
gpio_free(cs->line);
if (spi->dev.of_node)
kfree(cs);
}
spi_set_ctldata(spi, NULL);
}
@ -989,49 +1057,166 @@ static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
flush_fifo(sdd);
}
static int __devinit s3c64xx_spi_get_dmares(
struct s3c64xx_spi_driver_data *sdd, bool tx)
{
struct platform_device *pdev = sdd->pdev;
struct s3c64xx_spi_dma_data *dma_data;
struct property *prop;
struct resource *res;
char prop_name[15], *chan_str;
if (tx) {
dma_data = &sdd->tx_dma;
dma_data->direction = DMA_TO_DEVICE;
chan_str = "tx";
} else {
dma_data = &sdd->rx_dma;
dma_data->direction = DMA_FROM_DEVICE;
chan_str = "rx";
}
if (!sdd->pdev->dev.of_node) {
res = platform_get_resource(pdev, IORESOURCE_DMA, tx ? 0 : 1);
if (!res) {
dev_err(&pdev->dev, "Unable to get SPI-%s dma "
"resource\n", chan_str);
return -ENXIO;
}
dma_data->dmach = res->start;
return 0;
}
sprintf(prop_name, "%s-dma-channel", chan_str);
prop = of_find_property(pdev->dev.of_node, prop_name, NULL);
if (!prop) {
dev_err(&pdev->dev, "%s dma channel property not specified\n",
chan_str);
return -ENXIO;
}
dma_data->dmach = DMACH_DT_PROP;
dma_data->dma_prop = prop;
return 0;
}
#ifdef CONFIG_OF
static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
{
struct device *dev = &sdd->pdev->dev;
int idx, gpio, ret;
/* find gpios for mosi, miso and clock lines */
for (idx = 0; idx < 3; idx++) {
gpio = of_get_gpio(dev->of_node, idx);
if (!gpio_is_valid(gpio)) {
dev_err(dev, "invalid gpio[%d]: %d\n", idx, gpio);
goto free_gpio;
}
ret = gpio_request(gpio, "spi-bus");
if (ret) {
dev_err(dev, "gpio [%d] request failed\n", gpio);
goto free_gpio;
}
}
return 0;
free_gpio:
while (--idx >= 0)
gpio_free(sdd->gpios[idx]);
return -EINVAL;
}
static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
{
unsigned int idx;
for (idx = 0; idx < 3; idx++)
gpio_free(sdd->gpios[idx]);
}
static struct __devinit s3c64xx_spi_info * s3c64xx_spi_parse_dt(
struct device *dev)
{
struct s3c64xx_spi_info *sci;
u32 temp;
sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
if (!sci) {
dev_err(dev, "memory allocation for spi_info failed\n");
return ERR_PTR(-ENOMEM);
}
if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
dev_warn(dev, "spi bus clock parent not specified, using "
"clock at index 0 as parent\n");
sci->src_clk_nr = 0;
} else {
sci->src_clk_nr = temp;
}
if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
dev_warn(dev, "number of chip select lines not specified, "
"assuming 1 chip select line\n");
sci->num_cs = 1;
} else {
sci->num_cs = temp;
}
return sci;
}
#else
static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
{
return dev->platform_data;
}
static int s3c64xx_spi_parse_dt_gpio(struct s3c64xx_spi_driver_data *sdd)
{
return -EINVAL;
}
static void s3c64xx_spi_dt_gpio_free(struct s3c64xx_spi_driver_data *sdd)
{
}
#endif
static const struct of_device_id s3c64xx_spi_dt_match[];
static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
struct platform_device *pdev)
{
#ifdef CONFIG_OF
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
return (struct s3c64xx_spi_port_config *)match->data;
}
#endif
return (struct s3c64xx_spi_port_config *)
platform_get_device_id(pdev)->driver_data;
}
static int __init s3c64xx_spi_probe(struct platform_device *pdev)
{
struct resource *mem_res, *dmatx_res, *dmarx_res;
struct resource *mem_res;
struct s3c64xx_spi_driver_data *sdd;
struct s3c64xx_spi_info *sci;
struct s3c64xx_spi_info *sci = pdev->dev.platform_data;
struct spi_master *master;
int ret, irq;
char clk_name[16];
if (pdev->id < 0) {
dev_err(&pdev->dev,
"Invalid platform device id-%d\n", pdev->id);
return -ENODEV;
if (!sci && pdev->dev.of_node) {
sci = s3c64xx_spi_parse_dt(&pdev->dev);
if (IS_ERR(sci))
return PTR_ERR(sci);
}
if (pdev->dev.platform_data == NULL) {
if (!sci) {
dev_err(&pdev->dev, "platform_data missing!\n");
return -ENODEV;
}
sci = pdev->dev.platform_data;
/* Check for availability of necessary resource */
dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (dmatx_res == NULL) {
dev_err(&pdev->dev, "Unable to get SPI-Tx dma resource\n");
return -ENXIO;
}
dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (dmarx_res == NULL) {
dev_err(&pdev->dev, "Unable to get SPI-Rx dma resource\n");
return -ENXIO;
}
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (mem_res == NULL) {
dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
@ -1059,14 +1244,29 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
sdd->cntrlr_info = sci;
sdd->pdev = pdev;
sdd->sfr_start = mem_res->start;
sdd->tx_dma.dmach = dmatx_res->start;
sdd->tx_dma.direction = DMA_MEM_TO_DEV;
sdd->rx_dma.dmach = dmarx_res->start;
sdd->rx_dma.direction = DMA_DEV_TO_MEM;
sdd->port_id = pdev->id;
if (pdev->dev.of_node) {
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", ret);
goto err0;
}
sdd->port_id = ret;
} else {
sdd->port_id = pdev->id;
}
sdd->cur_bpw = 8;
ret = s3c64xx_spi_get_dmares(sdd, true);
if (ret)
goto err0;
ret = s3c64xx_spi_get_dmares(sdd, false);
if (ret)
goto err0;
master->dev.of_node = pdev->dev.of_node;
master->bus_num = sdd->port_id;
master->setup = s3c64xx_spi_setup;
master->cleanup = s3c64xx_spi_cleanup;
@ -1092,7 +1292,10 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
goto err1;
}
if (sci->cfg_gpio == NULL || sci->cfg_gpio()) {
if (!sci->cfg_gpio && pdev->dev.of_node) {
if (s3c64xx_spi_parse_dt_gpio(sdd))
return -EBUSY;
} else if (sci->cfg_gpio == NULL || sci->cfg_gpio()) {
dev_err(&pdev->dev, "Unable to config gpio\n");
ret = -EBUSY;
goto err2;
@ -1173,6 +1376,8 @@ err5:
err4:
clk_put(sdd->clk);
err3:
if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
s3c64xx_spi_dt_gpio_free(sdd);
err2:
iounmap((void *) sdd->regs);
err1:
@ -1204,6 +1409,9 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
clk_disable(sdd->clk);
clk_put(sdd->clk);
if (!sdd->cntrlr_info->cfg_gpio && pdev->dev.of_node)
s3c64xx_spi_dt_gpio_free(sdd);
iounmap((void *) sdd->regs);
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@ -1228,6 +1436,9 @@ static int s3c64xx_spi_suspend(struct device *dev)
clk_disable(sdd->src_clk);
clk_disable(sdd->clk);
if (!sdd->cntrlr_info->cfg_gpio && dev->of_node)
s3c64xx_spi_dt_gpio_free(sdd);
sdd->cur_speed = 0; /* Output Clock is stopped */
return 0;
@ -1239,7 +1450,10 @@ static int s3c64xx_spi_resume(struct device *dev)
struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
sci->cfg_gpio();
if (!sci->cfg_gpio && dev->of_node)
s3c64xx_spi_parse_dt_gpio(sdd);
else
sci->cfg_gpio();
/* Enable the clock */
clk_enable(sdd->src_clk);
@ -1347,11 +1561,22 @@ static struct platform_device_id s3c64xx_spi_driver_ids[] = {
{ },
};
#ifdef CONFIG_OF
static const struct of_device_id s3c64xx_spi_dt_match[] = {
{ .compatible = "samsung,exynos4210-spi",
.data = (void *)&exynos4_spi_port_config,
},
{ },
};
MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
#endif /* CONFIG_OF */
static struct platform_driver s3c64xx_spi_driver = {
.driver = {
.name = "s3c64xx-spi",
.owner = THIS_MODULE,
.pm = &s3c64xx_spi_pm,
.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
},
.remove = s3c64xx_spi_remove,
.id_table = s3c64xx_spi_driver_ids,