[PATCH 4/5] mmc: mvsdio: implement a Device Tree binding
Andrew Lunn
andrew at lunn.ch
Wed Jan 16 08:13:59 EST 2013
From: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
This patch adds a simple Device Tree binding for the mvsdio driver, as
well as the necessary documentation for it. Compatibility with non-DT
platforms is preserved, by keeping the platform_data based
initialization.
We introduce a small difference between non-DT and DT platforms: DT
platforms are required to provide a clocks = <...> property, which the
driver uses to get the frequency of the clock that goes to the SDIO
IP. The behaviour on non-DT platforms is kept unchanged: a clock
reference is not mandatory, but the clock frequency must be passed in
the "clock" field of the mvsdio_platform_data structure.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Signed-off-by: Andrew Lunn <andrew at lunn.ch>
Tested-by: Stefan Peter <s.peter at mpl.ch>
Tested-by: Florian Fainelli <florian at openwrt.org>
Signed-off-by: Jason Cooper <jason at lakedaemon.net>
---
.../devicetree/bindings/mmc/orion-sdio.txt | 17 ++++++
drivers/mmc/host/mvsdio.c | 62 +++++++++++++++-----
2 files changed, 64 insertions(+), 15 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mmc/orion-sdio.txt
diff --git a/Documentation/devicetree/bindings/mmc/orion-sdio.txt b/Documentation/devicetree/bindings/mmc/orion-sdio.txt
new file mode 100644
index 0000000..84f0ebd
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/orion-sdio.txt
@@ -0,0 +1,17 @@
+* Marvell orion-sdio controller
+
+This file documents differences between the core properties in mmc.txt
+and the properties used by the orion-sdio driver.
+
+- compatible: Should be "marvell,orion-sdio"
+- clocks: reference to the clock of the SDIO interface
+
+Example:
+
+ mvsdio at d00d4000 {
+ compatible = "marvell,orion-sdio";
+ reg = <0xd00d4000 0x200>;
+ interrupts = <54>;
+ clocks = <&gateclk 17>;
+ status = "disabled";
+ };
diff --git a/drivers/mmc/host/mvsdio.c b/drivers/mmc/host/mvsdio.c
index 704b7a3..5ea0b96 100644
--- a/drivers/mmc/host/mvsdio.c
+++ b/drivers/mmc/host/mvsdio.c
@@ -21,6 +21,8 @@
#include <linux/irq.h>
#include <linux/clk.h>
#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
#include <linux/mmc/host.h>
#include <linux/mmc/slot-gpio.h>
@@ -681,17 +683,17 @@ mv_conf_mbus_windows(struct mvsd_host *host,
static int __init mvsd_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
struct mmc_host *mmc = NULL;
struct mvsd_host *host = NULL;
- const struct mvsdio_platform_data *mvsd_data;
const struct mbus_dram_target_info *dram;
struct resource *r;
int ret, irq;
+ int gpio_card_detect, gpio_write_protect;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
- mvsd_data = pdev->dev.platform_data;
- if (!r || irq < 0 || !mvsd_data)
+ if (!r || irq < 0)
return -ENXIO;
mmc = mmc_alloc_host(sizeof(struct mvsd_host), &pdev->dev);
@@ -703,8 +705,37 @@ static int __init mvsd_probe(struct platform_device *pdev)
host = mmc_priv(mmc);
host->mmc = mmc;
host->dev = &pdev->dev;
- host->base_clock = mvsd_data->clock / 2;
- host->clk = ERR_PTR(-EINVAL);
+
+ /* Some non-DT platforms do not pass a clock, and the clock
+ frequency is passed through platform_data. On DT platforms,
+ a clock must always be passed, even if there is no gatable
+ clock associated to the SDIO interface (it can simply be a
+ fixed rate clock). */
+ host->clk = devm_clk_get(&pdev->dev, NULL);
+ if (!IS_ERR(host->clk))
+ clk_prepare_enable(host->clk);
+
+ if (np) {
+ if (IS_ERR(host->clk)) {
+ dev_err(&pdev->dev, "DT platforms must have a clock associated\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ host->base_clock = clk_get_rate(host->clk) / 2;
+ gpio_card_detect = of_get_named_gpio(np, "cd-gpios", 0);
+ gpio_write_protect = of_get_named_gpio(np, "wp-gpios", 0);
+ } else {
+ const struct mvsdio_platform_data *mvsd_data;
+ mvsd_data = pdev->dev.platform_data;
+ if (!mvsd_data) {
+ ret = -ENXIO;
+ goto out;
+ }
+ host->base_clock = mvsd_data->clock / 2;
+ gpio_card_detect = mvsd_data->gpio_card_detect;
+ gpio_write_protect = mvsd_data->gpio_write_protect;
+ }
mmc->ops = &mvsd_ops;
@@ -743,20 +774,14 @@ static int __init mvsd_probe(struct platform_device *pdev)
goto out;
}
- /* Not all platforms can gate the clock, so it is not
- an error if the clock does not exists. */
- host->clk = devm_clk_get(&pdev->dev, NULL);
- if (!IS_ERR(host->clk))
- clk_prepare_enable(host->clk);
-
- if (gpio_is_valid(mvsd_data->gpio_card_detect)) {
- ret = mmc_gpio_request_cd(mmc, mvsd_data->gpio_card_detect);
+ if (gpio_is_valid(gpio_card_detect)) {
+ ret = mmc_gpio_request_cd(mmc, gpio_card_detect);
if (ret)
goto out;
} else
mmc->caps |= MMC_CAP_NEEDS_POLL;
- mmc_gpio_request_ro(mmc, mvsd_data->gpio_write_protect);
+ mmc_gpio_request_ro(mmc, gpio_write_protect);
setup_timer(&host->timer, mvsd_timeout_timer, (unsigned long)host);
platform_set_drvdata(pdev, mmc);
@@ -768,7 +793,7 @@ static int __init mvsd_probe(struct platform_device *pdev)
mmc_hostname(mmc), DRIVER_NAME);
if (!(mmc->caps & MMC_CAP_NEEDS_POLL))
printk("using GPIO %d for card detection\n",
- mvsd_data->gpio_card_detect);
+ gpio_card_detect);
else
printk("lacking card detect (fall back to polling)\n");
return 0;
@@ -832,12 +857,19 @@ static int mvsd_resume(struct platform_device *dev)
#define mvsd_resume NULL
#endif
+static const struct of_device_id mvsdio_dt_ids[] = {
+ { .compatible = "marvell,orion-sdio" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mvsdio_dt_ids);
+
static struct platform_driver mvsd_driver = {
.remove = __exit_p(mvsd_remove),
.suspend = mvsd_suspend,
.resume = mvsd_resume,
.driver = {
.name = DRIVER_NAME,
+ .of_match_table = mvsdio_dt_ids,
},
};
--
1.7.10.4
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