[PATCH v2 2/3] mmc: davinci_mmc: add DT support

From: Manjunathappa, Prakash
Date: Thu Feb 07 2013 - 02:56:39 EST


Adds device tree support for davinci_mmc. Also add binding documentation.
Tested in non-dma PIO mode and without GPIO card_detect/write_protect
option because of dependencies on EDMA and GPIO module DT support.

Signed-off-by: Manjunathappa, Prakash <prakash.pm@xxxxxx>
Cc: linux-mmc@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: davinci-linux-open-source@xxxxxxxxxxxxxxxxxxxx
Cc: devicetree-discuss@xxxxxxxxxxxxxxxx
Cc: cjb@xxxxxxxxxx
Cc: Sekhar Nori <nsekhar@xxxxxx>
Cc: mporter@xxxxxx
---
Since v1:
Modified DT parse function to take default values and accomodate controller
version in compatible field.

.../devicetree/bindings/mmc/davinci_mmc.txt | 30 ++++++++
drivers/mmc/host/davinci_mmc.c | 70 +++++++++++++++++++-
2 files changed, 99 insertions(+), 1 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mmc/davinci_mmc.txt

diff --git a/Documentation/devicetree/bindings/mmc/davinci_mmc.txt b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt
new file mode 100644
index 0000000..6717ab1
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt
@@ -0,0 +1,30 @@
+* TI Highspeed MMC host controller for DaVinci
+
+The Highspeed MMC Host Controller on TI DaVinci family
+provides an interface for MMC, SD and SDIO types of memory cards.
+
+This file documents the properties used by the davinci_mmc driver.
+
+Required properties:
+- compatible:
+ Should be "ti,davinci-mmc-da830": for da830, da850, dm365
+ Should be "ti,davinci-mmc-dm355": for dm355, dm644x
+
+Optional properties:
+- bus-width: Number of data lines, can be <4>, or <8>, default <1>
+- max-frequency: Maximum operating clock frequency, default 25MHz.
+- mmc-cap-mmc-highspeed: Indicates support for MMC in high speed mode
+- mmc-cap-sd-highspeed: Indicates support for SD in high speed mode
+
+Example:
+ mmc0: mmc@1c40000 {
+ compatible = "ti,davinci-mmc-da830",
+ reg = <0x40000 0x1000>;
+ interrupts = <16>;
+ status = "okay";
+ bus-width = <4>;
+ max-frequency = <50000000>;
+ mmc-cap-sd-highspeed;
+ mmc-cap-mmc-highspeed;
+ };
+
diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 27123f8..3f90316 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -34,6 +34,8 @@
#include <linux/dma-mapping.h>
#include <linux/edma.h>
#include <linux/mmc/mmc.h>
+#include <linux/of.h>
+#include <linux/of_device.h>

#include <linux/platform_data/mmc-davinci.h>

@@ -1157,15 +1159,80 @@ static void __init init_mmcsd_host(struct mmc_davinci_host *host)
mmc_davinci_reset_ctrl(host, 0);
}

-static int __init davinci_mmcsd_probe(struct platform_device *pdev)
+static const struct of_device_id davinci_mmc_dt_ids[] = {
+ {
+ .compatible = "ti,davinci-mmc-dm355",
+ .data = (void *)MMC_CTLR_VERSION_1,
+ },
+ {
+ .compatible = "ti,davinci-mmc-da830",
+ .data = (void *)MMC_CTLR_VERSION_2,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, davinci_mmc_dt_ids);
+
+static struct davinci_mmc_config
+ *mmc_parse_pdata(struct platform_device *pdev)
{
+ struct device_node *np;
struct davinci_mmc_config *pdata = pdev->dev.platform_data;
+ const struct of_device_id *match =
+ of_match_device(of_match_ptr(davinci_mmc_dt_ids), &pdev->dev);
+ u32 data;
+
+ np = pdev->dev.of_node;
+ if (!np)
+ return pdata;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n");
+ goto nodata;
+ }
+
+ if (match->data)
+ pdata->version = (u8)((int)match->data);
+
+ of_property_read_u32(np, "max-frequency", &pdata->max_freq);
+ if (!pdata->max_freq)
+ dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
+
+ if (of_get_property(np, "mmc-cap-mmc-highspeed", NULL))
+ pdata->caps |= MMC_CAP_MMC_HIGHSPEED;
+ if (of_get_property(np, "mmc-cap-sd-highspeed", NULL))
+ pdata->caps |= MMC_CAP_SD_HIGHSPEED;
+
+ of_property_read_u32(np, "bus-width", &data);
+ switch (data) {
+ case 0:
+ case 4:
+ case 8:
+ pdata->wires = data;
+ break;
+ default:
+ pdata->wires = 1;
+ dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n");
+ }
+nodata:
+ return pdata;
+}
+
+static int __init davinci_mmcsd_probe(struct platform_device *pdev)
+{
+ struct davinci_mmc_config *pdata = NULL;
struct mmc_davinci_host *host = NULL;
struct mmc_host *mmc = NULL;
struct resource *r, *mem = NULL;
int ret = 0, irq = 0;
size_t mem_size;

+ pdata = mmc_parse_pdata(pdev);
+ if (pdata == NULL) {
+ dev_err(&pdev->dev, "Can not get platform data\n");
+ return -ENOENT;
+ }
+
/* REVISIT: when we're fully converted, fail if pdata is NULL */

ret = -ENODEV;
@@ -1408,6 +1475,7 @@ static struct platform_driver davinci_mmcsd_driver = {
.name = "davinci_mmc",
.owner = THIS_MODULE,
.pm = davinci_mmcsd_pm_ops,
+ .of_match_table = of_match_ptr(davinci_mmc_dt_ids),
},
.remove = __exit_p(davinci_mmcsd_remove),
};
--
1.7.4.1

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