[PATCH 1/4] mmc: atmel-mci: add device tree support
ludovic.desroches at atmel.com
ludovic.desroches at atmel.com
Wed Mar 21 14:03:11 EDT 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 | 55 +++++++++++++++
drivers/mmc/host/atmel-mci.c | 74 +++++++++++++++++++-
2 files changed, 126 insertions(+), 3 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..657f9de
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/atmel-hsmci.txt
@@ -0,0 +1,55 @@
+* 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
+- 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>;
+
+ [ child node definitions...]
+};
+
+2) slot nodes
+
+Optional properties:
+- bus-width: number of data lines connected to the controller
+- cd-gpios: specify GPIOs for card detection
+- cd-invert: invert the value of external card detect gpio line
+- wp-gpios: specify GPIOs for write protection
+
+Example slot node:
+
+slot at 0 {
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-invert;
+};
+
+Example full MCI node:
+mmc0: mmc at f0008000 {
+ compatible = "atmel,hsmci";
+ reg = <0xf0008000 0x600>;
+ interrupts = <12 4>;
+ slot at 0 {
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-invert;
+ };
+ slot at 1 {
+ bus-width = <4>;
+ };
+};
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index b5693fd..2d6a04a 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>
@@ -477,6 +480,54 @@ 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 void __init
+atmci_get_of_slots(struct device *dev, struct mci_platform_data *pdata)
+{
+ struct device_node *np = dev->of_node;
+ struct device_node *cnp;
+ unsigned int slot_nb = 0;
+
+ if (!np)
+ return;
+
+ for_each_child_of_node(np, cnp) {
+ if (slot_nb > (ATMCI_MAX_NR_SLOTS-1)) {
+ dev_warn(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_nb].bus_width))
+ pdata->slot[slot_nb].bus_width = 1;
+
+ pdata->slot[slot_nb].detect_pin =
+ of_get_named_gpio(cnp, "cd-gpios", 0);
+
+ if (of_find_property(cnp, "cd-invert", NULL))
+ pdata->slot[slot_nb].detect_is_active_high = true;
+
+ pdata->slot[slot_nb].wp_pin =
+ of_get_named_gpio(cnp, "wp-gpios", 0);
+
+ slot_nb++;
+ }
+}
+#else /* CONFIG_OF */
+static inline void
+atmci_get_of_slots(struct device *dev, struct mci_platform_data *pdata)
+{
+ return;
+}
+#endif
+
static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
unsigned int ns)
{
@@ -1847,6 +1898,13 @@ 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;
@@ -2047,9 +2105,17 @@ static int __init atmci_probe(struct platform_device *pdev)
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
return -ENXIO;
- pdata = pdev->dev.platform_data;
- if (!pdata)
- return -ENXIO;
+
+ if (pdev->dev.of_node) {
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+ } else {
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+ }
+
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
@@ -2109,6 +2175,7 @@ static int __init atmci_probe(struct platform_device *pdev)
/* We need at least one slot to succeed */
nr_slots = 0;
ret = -ENODEV;
+ atmci_get_of_slots(&pdev->dev, pdata);
if (pdata->slot[0].bus_width) {
ret = atmci_init_slot(host, &pdata->slot[0],
0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
@@ -2242,6 +2309,7 @@ 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
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