[PATCH v6 6/9] mmc: dw_mmc: add device tree support
Thomas Abraham
thomas.abraham at linaro.org
Tue Sep 18 04:16:40 EST 2012
Add device tree based discovery support.
Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
Acked-by: Will Newton <will.newton at imgtec.com>
---
.../devicetree/bindings/mmc/synposis-dw-mshc.txt | 79 ++++++++++++
drivers/mmc/host/dw_mmc-pltfm.c | 9 ++
drivers/mmc/host/dw_mmc.c | 130 ++++++++++++++++++-
3 files changed, 211 insertions(+), 7 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
diff --git a/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
new file mode 100644
index 0000000..06cd32d
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/synposis-dw-mshc.txt
@@ -0,0 +1,79 @@
+* Synopsis Designware Mobile Storage Host Controller
+
+The Synopsis designware mobile storage host controller is used to interface
+a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
+differences between the core mmc properties described by mmc.txt and the
+properties used by the Synopsis Designware Mobile Storage Host Controller.
+
+Required Properties:
+
+* compatible: should be
+ - snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
+* #address-cells: should be 1.
+* #size-cells: should be 0.
+
+# Slots: The slot specific information are contained within child-nodes with
+ each child-node representing a supported slot. There should be atleast one
+ child node representing a card slot. The name of the child node representing
+ the slot is recommended to be slot at n where n is the unique number of the slot
+ connnected to the controller. The following are optional properties which
+ can be included in the slot child node.
+
+ * reg: specifies the physical slot number. The valid values of this
+ property is 0 to (num-slots -1), where num-slots is the value
+ specified by the num-slots property.
+
+ * bus-width: as documented in mmc core bindings.
+
+ * wp-gpios: specifies the write protect gpio line. The format of the
+ gpio specifier depends on the gpio controller. If the write-protect
+ line is not available, this property is optional.
+
+Optional properties:
+
+* num-slots: specifies the number of slots supported by the controller.
+ The number of physical slots actually used could be equal or less than the
+ value specified by num-slots. If this property is not specified, the value
+ of num-slot property is assumed to be 1.
+
+* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
+ specified, the default value of the fifo size is determined from the
+ controller registers.
+
+* card-detect-delay: Delay in milli-seconds before detecting card after card
+ insert event. The default value is 0.
+
+* supports-highspeed: Enables support for high speed cards (upto 50MHz)
+
+* broken-cd: as documented in mmc core bindings.
+
+Aliases:
+
+- All the MSHC controller nodes should be represented in the aliases node using
+ the following format 'mshc{n}' where n is a unique number for the alias.
+
+Example:
+
+The MSHC controller node can be split into two portions, SoC specific and
+board specific portions as listed below.
+
+ dwmmc0 at 12200000 {
+ compatible = "snps,dw-mshc";
+ reg = <0x12200000 0x1000>;
+ interrupts = <0 75 0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ dwmmc0 at 12200000 {
+ num-slots = <1>;
+ supports-highspeed;
+ broken-cd;
+ fifo-depth = <0x80>;
+ card-detect-delay = <200>;
+
+ slot at 0 {
+ reg = <0>;
+ bus-width = <8>;
+ };
+ };
diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c
index ce7be1a..7205905 100644
--- a/drivers/mmc/host/dw_mmc-pltfm.c
+++ b/drivers/mmc/host/dw_mmc-pltfm.c
@@ -19,6 +19,8 @@
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/dw_mmc.h>
+#include <linux/of.h>
+
#include "dw_mmc.h"
static int __devinit dw_mci_pltfm_probe(struct platform_device *pdev)
@@ -94,10 +96,17 @@ static int dw_mci_pltfm_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(dw_mci_pltfm_pmops, dw_mci_pltfm_suspend, dw_mci_pltfm_resume);
+static const struct of_device_id dw_mci_pltfm_match[] = {
+ { .compatible = "snps,dw-mshc", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, dw_mci_pltfm_match);
+
static struct platform_driver dw_mci_pltfm_driver = {
.remove = __exit_p(dw_mci_pltfm_remove),
.driver = {
.name = "dw_mmc",
+ .of_match_table = of_match_ptr(dw_mci_pltfm_match),
.pm = &dw_mci_pltfm_pmops,
},
};
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 455a155..c792466 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -33,6 +33,7 @@
#include <linux/bitops.h>
#include <linux/regulator/consumer.h>
#include <linux/workqueue.h>
+#include <linux/of.h>
#include "dw_mmc.h"
@@ -1769,10 +1770,57 @@ static void dw_mci_work_routine_card(struct work_struct *work)
}
}
+#ifdef CONFIG_OF
+/* given a slot id, find out the device node representing that slot */
+static struct device_node *dw_mci_of_find_slot_node(struct device *dev, u8 slot)
+{
+ struct device_node *np;
+ const __be32 *addr;
+ int len;
+
+ if (!dev || !dev->of_node)
+ return NULL;
+
+ for_each_child_of_node(dev->of_node, np) {
+ addr = of_get_property(np, "reg", &len);
+ if (!addr || (len < sizeof(int)))
+ continue;
+ if (be32_to_cpup(addr) == slot)
+ return np;
+ }
+ return NULL;
+}
+
+/* find out bus-width for a given slot */
+static u32 dw_mci_of_get_bus_wd(struct device *dev, u8 slot)
+{
+ struct device_node *np = dw_mci_of_find_slot_node(dev, slot);
+ u32 bus_wd = 1;
+
+ if (!np)
+ return 1;
+
+ if (of_property_read_u32(np, "bus-width", &bus_wd))
+ dev_err(dev, "bus-width property not found, assuming width"
+ " as 1\n");
+ return bus_wd;
+}
+#else /* CONFIG_OF */
+static u32 dw_mci_of_get_bus_wd(struct device *dev, u8 slot)
+{
+ return 1;
+}
+static struct device_node *dw_mci_of_find_slot_node(struct device *dev, u8 slot)
+{
+ return NULL;
+}
+#endif /* CONFIG_OF */
+
static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
{
struct mmc_host *mmc;
struct dw_mci_slot *slot;
+ u8 bus_width;
mmc = mmc_alloc_host(sizeof(struct dw_mci_slot), host->dev);
if (!mmc)
@@ -1782,6 +1830,7 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
slot->id = id;
slot->mmc = mmc;
slot->host = host;
+ host->slot[id] = slot;
mmc->ops = &dw_mci_ops;
mmc->f_min = DIV_ROUND_UP(host->bus_hz, 510);
@@ -1806,8 +1855,18 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
mmc->caps2 = host->pdata->caps2;
if (host->pdata->get_bus_wd)
- if (host->pdata->get_bus_wd(slot->id) >= 4)
- mmc->caps |= MMC_CAP_4_BIT_DATA;
+ bus_width = host->pdata->get_bus_wd(slot->id);
+ else if (host->dev->of_node)
+ bus_width = dw_mci_of_get_bus_wd(host->dev, slot->id);
+ else
+ bus_width = 1;
+
+ switch (bus_width) {
+ case 8:
+ mmc->caps |= MMC_CAP_8_BIT_DATA;
+ case 4:
+ mmc->caps |= MMC_CAP_4_BIT_DATA;
+ }
if (host->pdata->quirks & DW_MCI_QUIRK_HIGHSPEED)
mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED;
@@ -1852,7 +1911,6 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
else
clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
- host->slot[id] = slot;
mmc_add_host(mmc);
#if defined(CONFIG_DEBUG_FS)
@@ -1944,16 +2002,74 @@ static bool mci_wait_reset(struct device *dev, struct dw_mci *host)
return false;
}
+#ifdef CONFIG_OF
+static struct dw_mci_of_quirks {
+ char *quirk;
+ int id;
+} of_quirks[] = {
+ {
+ .quirk = "supports-highspeed",
+ .id = DW_MCI_QUIRK_HIGHSPEED,
+ }, {
+ .quirk = "broken-cd",
+ .id = DW_MCI_QUIRK_BROKEN_CARD_DETECTION,
+ },
+};
+
+static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
+{
+ struct dw_mci_board *pdata;
+ struct device *dev = host->dev;
+ struct device_node *np = dev->of_node;
+ int idx;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(dev, "could not allocate memory for pdata\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* find out number of slots supported */
+ if (of_property_read_u32(dev->of_node, "num-slots",
+ &pdata->num_slots)) {
+ dev_info(dev, "num-slots property not found, "
+ "assuming 1 slot is available\n");
+ pdata->num_slots = 1;
+ }
+
+ /* get quirks */
+ for (idx = 0; idx < ARRAY_SIZE(of_quirks); idx++)
+ if (of_get_property(np, of_quirks[idx].quirk, NULL))
+ pdata->quirks |= of_quirks[idx].id;
+
+ if (of_property_read_u32(np, "fifo-depth", &pdata->fifo_depth))
+ dev_info(dev, "fifo-depth property not found, using "
+ "value of FIFOTH register as default\n");
+
+ of_property_read_u32(np, "card-detect-delay", &pdata->detect_delay_ms);
+
+ return pdata;
+}
+
+#else /* CONFIG_OF */
+static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
+{
+ return ERR_PTR(-EINVAL);
+}
+#endif /* CONFIG_OF */
+
int dw_mci_probe(struct dw_mci *host)
{
int width, i, ret = 0;
u32 fifo_size;
int init_slots = 0;
- if (!host->pdata || !host->pdata->init) {
- dev_err(host->dev,
- "Platform data must supply init function\n");
- return -ENODEV;
+ if (!host->pdata) {
+ host->pdata = dw_mci_parse_dt(host);
+ if (IS_ERR(host->pdata)) {
+ dev_err(host->dev, "platform data not available\n");
+ return -EINVAL;
+ }
}
if (!host->pdata->select_slot && host->pdata->num_slots > 1) {
--
1.6.6.rc2
More information about the devicetree-discuss
mailing list