[PATCH v4 1/3] mmc: atmel-mci: add device tree support
ludovic.desroches at atmel.com
ludovic.desroches at atmel.com
Wed May 23 17:23:50 EST 2012
From: Ludovic Desroches <ludovic.desroches at atmel.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
---
.../devicetree/bindings/mmc/atmel-hsmci.txt | 67 +++++++++++++++
drivers/mmc/host/atmel-mci.c | 87 +++++++++++++++++++-
2 files changed, 152 insertions(+), 2 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
diff --git a/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt b/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
new file mode 100644
index 0000000..81c20cc
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
@@ -0,0 +1,67 @@
+* Atmel High Speed MultiMedia Card Interface
+
+This controller on atmel products provides an interface for MMC, SD and SDIO
+types of memory cards.
+
+1) MCI node
+
+Required properties:
+- compatible: no blank "atmel,hsmci"
+- reg: should contain HSMCI registers location and length
+- interrupts: should contain HSMCI interrupt number
+- #address-cells: should be one. The cell is the slot id.
+- #size-cells: should be zero.
+- at least one slot node
+
+The node contains child nodes for each slot that the platform uses
+
+Example MCI node:
+
+mmc0: mmc at f0008000 {
+ compatible = "atmel,hsmci";
+ reg = <0xf0008000 0x600>;
+ interrupts = <12 4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ [ child node definitions...]
+};
+
+2) slot nodes
+
+Required properties:
+- reg: should contain the slot id.
+- bus-width: number of data lines connected to the controller
+
+Optional properties:
+- cd-gpios: specify GPIOs for card detection
+- cd-inverted: invert the value of external card detect gpio line
+- wp-gpios: specify GPIOs for write protection
+
+Example slot node:
+
+slot at 0 {
+ reg = <0>;
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-inverted;
+};
+
+Example full MCI node:
+mmc0: mmc at f0008000 {
+ compatible = "atmel,hsmci";
+ reg = <0xf0008000 0x600>;
+ interrupts = <12 4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ slot at 0 {
+ reg = <0>;
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-inverted;
+ };
+ slot at 1 {
+ reg = <1>;
+ bus-width = <4>;
+ };
+};
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 556d384..1842dc7 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -19,6 +19,9 @@
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/seq_file.h>
@@ -493,6 +496,72 @@ err:
dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
}
+#if defined(CONFIG_OF)
+static const struct of_device_id atmci_dt_ids[] = {
+ { .compatible = "atmel,hsmci" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmci_dt_ids);
+
+static struct mci_platform_data __devinit*
+atmci_of_init(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *cnp;
+ struct mci_platform_data *pdata;
+ u32 slot_id;
+ int ret;
+
+ if (!np) {
+ dev_err(&pdev->dev, "device node not found\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(&pdev->dev, "could not allocate memory for pdata\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ for_each_child_of_node(np, cnp) {
+ ret = of_property_read_u32(cnp, "reg", &slot_id);
+ if (ret) {
+ dev_warn(&pdev->dev, "reg property is missing for %s\n",
+ cnp->full_name);
+ continue;
+ }
+
+ if (slot_id > (ATMCI_MAX_NR_SLOTS-1)) {
+ dev_warn(&pdev->dev, "can't have more than %d slots\n",
+ ATMCI_MAX_NR_SLOTS);
+ break;
+ }
+
+ if (of_property_read_u32(cnp, "bus-width",
+ &pdata->slot[slot_id].bus_width))
+ pdata->slot[slot_id].bus_width = 1;
+
+ pdata->slot[slot_id].detect_pin =
+ of_get_named_gpio(cnp, "cd-gpios", 0);
+
+ pdata->slot[slot_id].detect_is_active_high =
+ of_property_read_bool(cnp, "cd-inverted");
+
+ pdata->slot[slot_id].wp_pin =
+ of_get_named_gpio(cnp, "wp-gpios", 0);
+ }
+
+ return pdata;
+}
+#else /* CONFIG_OF */
+static inline struct mci_platform_data*
+atmci_of_init(struct platform_device *dev)
+{
+ return ERR_PTR(-EINVAL);
+}
+#endif
+
static inline unsigned int atmci_get_version(struct atmel_mci *host)
{
return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
@@ -2038,6 +2107,13 @@ static int __init atmci_init_slot(struct atmel_mci *host,
slot->sdc_reg = sdc_reg;
slot->sdio_irq = sdio_irq;
+ dev_dbg(&mmc->class_dev,
+ "slot[%u]: bus_width=%u, detect_pin=%d, "
+ "detect_is_active_high=%s, wp_pin=%d\n",
+ id, slot_data->bus_width, slot_data->detect_pin,
+ slot_data->detect_is_active_high ? "true" : "false",
+ slot_data->wp_pin);
+
mmc->ops = &atmci_ops;
mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
mmc->f_max = host->bus_hz / 2;
@@ -2258,8 +2334,14 @@ static int __init atmci_probe(struct platform_device *pdev)
if (!regs)
return -ENXIO;
pdata = pdev->dev.platform_data;
- if (!pdata)
- return -ENXIO;
+ if (!pdata) {
+ pdata = atmci_of_init(pdev);
+ if (IS_ERR(pdata)) {
+ dev_err(&pdev->dev, "platform data not available\n");
+ return PTR_ERR(pdata);
+ }
+ }
+
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
@@ -2477,6 +2559,7 @@ static struct platform_driver atmci_driver = {
.driver = {
.name = "atmel_mci",
.pm = ATMCI_PM_OPS,
+ .of_match_table = of_match_ptr(atmci_dt_ids),
},
};
--
1.7.5.4
More information about the devicetree-discuss
mailing list