[PATCH v7 3/5] mmc: davinci_mmc: add DT support
Manjunathappa, Prakash
prakash.pm at ti.com
Fri Mar 29 00:12:00 EST 2013
Adds device tree support for davinci_mmc. Also add binding documentation.
As of now tested for 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 at ti.com>
Reviewed-by: Mark Rutland <mark.rutland at arm.com>
Tested-by: Sekhar Nori <nsekhar at ti.com>
Cc: linux-mmc at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: davinci-linux-open-source at linux.davincidsp.com
Cc: devicetree-discuss at lists.ozlabs.org
Cc: cjb at laptop.org
Cc: Sekhar Nori <nsekhar at ti.com>
Cc: mporter at ti.com
Cc: Arnd Bergmann <arnd at arndb.de>
---
Since v6:
Add DMA handling capability.
Since v4:
Minor nit, check on return value for failure of max-frequency property
parsing.
Since v2:
Modified the default value for bus-width and skipping the property specifications for highspeed card capabilties for now. Re-ordered patch 2 and 3.
Since v1:
Modified the DT parse function to take default values, updated DT binding documentation accordingly.
.../devicetree/bindings/mmc/davinci_mmc.txt | 33 +++++++++
drivers/mmc/host/davinci_mmc.c | 70 ++++++++++++++++++-
2 files changed, 99 insertions(+), 4 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..e5a0140
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt
@@ -0,0 +1,33 @@
+* 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,da830-mmc": for da830, da850, dm365
+ Should be "ti,dm355-mmc": for dm355, dm644x
+
+Optional properties:
+- bus-width: Number of data lines, can be <1>, <4>, or <8>, default <1>
+- max-frequency: Maximum operating clock frequency, default 25MHz.
+- dmas: List of DMA specifiers with the controller specific format
+ as described in the generic DMA client binding. A tx and rx
+ specifier is required.
+- dma-names: RX and TX DMA request names. These strings correspond
+ 1:1 with the DMA specifiers listed in dmas.
+
+Example:
+mmc0: mmc at 1c40000 {
+ compatible = "ti,da830-mmc",
+ reg = <0x40000 0x1000>;
+ interrupts = <16>;
+ status = "okay";
+ bus-width = <4>;
+ max-frequency = <50000000>;
+ dmas = <&edma 16
+ &edma 17>;
+ dma-names = "rx", "tx";
+};
diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 7d0e684..1d06e5a 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/edma.h>
#include <linux/platform_data/mmc-davinci.h>
@@ -523,14 +525,16 @@ static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
dma_cap_set(DMA_SLAVE, mask);
host->dma_tx =
- dma_request_channel(mask, edma_filter_fn, &host->txdma);
+ dma_request_slave_channel_compat(mask, edma_filter_fn,
+ &host->txdma, mmc_dev(host->mmc), "tx");
if (!host->dma_tx) {
dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
return -ENODEV;
}
host->dma_rx =
- dma_request_channel(mask, edma_filter_fn, &host->rxdma);
+ dma_request_slave_channel_compat(mask, edma_filter_fn,
+ &host->rxdma, mmc_dev(host->mmc), "rx");
if (!host->dma_rx) {
dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
r = -ENODEV;
@@ -1170,9 +1174,62 @@ static struct platform_device_id davinci_mmc_devtype[] = {
};
MODULE_DEVICE_TABLE(platform, davinci_mmc_devtype);
-static int __init davinci_mmcsd_probe(struct platform_device *pdev)
+static const struct of_device_id davinci_mmc_dt_ids[] = {
+ {
+ .compatible = "ti,dm6441-mmc",
+ .data = &davinci_mmc_devtype[MMC_CTLR_VERSION_1],
+ },
+ {
+ .compatible = "ti,da830-mmc",
+ .data = &davinci_mmc_devtype[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)
+ pdev->id_entry = match->data;
+
+ if (of_property_read_u32(np, "max-frequency", &pdata->max_freq))
+ dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n");
+
+ of_property_read_u32(np, "bus-width", &data);
+ switch (data) {
+ case 1:
+ 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;
@@ -1180,7 +1237,11 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
size_t mem_size;
const struct platform_device_id *id_entry;
- /* REVISIT: when we're fully converted, fail if pdata is NULL */
+ pdata = mmc_parse_pdata(pdev);
+ if (pdata == NULL) {
+ dev_err(&pdev->dev, "Couldn't get platform data\n");
+ return -ENOENT;
+ }
ret = -ENODEV;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1424,6 +1485,7 @@ 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),
.id_table = davinci_mmc_devtype,
--
1.7.4.1
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