[PATCH] MTD: Add device-tree support to fsmc_nand
Stefan Roese
sr at denx.de
Fri Mar 16 20:19:31 EST 2012
This patch adds support to configure the FSMC NAND driver (used amongst
others on SPEAr platforms) via device-tree instead of platform_data.
Signed-off-by: Stefan Roese <sr at denx.de>
Cc: Viresh Kumar <viresh.kumar at st.com>
---
.../devicetree/bindings/mtd/fsmc-nand.txt | 33 ++++++++++++
drivers/mtd/nand/fsmc_nand.c | 57 +++++++++++++++++++-
include/linux/mtd/fsmc.h | 4 +-
3 files changed, 91 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mtd/fsmc-nand.txt
diff --git a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
new file mode 100644
index 0000000..e2c663b
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
@@ -0,0 +1,33 @@
+* FSMC NAND
+
+Required properties:
+- compatible : "st,spear600-fsmc-nand"
+- reg : Address range of the mtd chip
+- reg-names: Should contain the reg names "fsmc_regs" and "nand_data"
+- st,ale-off : Chip specific offset to ALE
+- st,cle-off : Chip specific offset to CLE
+
+Optional properties:
+- bank-width : Width (in bytes) of the device. If not present, the width
+ defaults to 1 byte
+- nand-skip-bbtscan: Indicates the the BBT scanning should be skipped
+
+Example:
+
+ fsmc: flash at d1800000 {
+ compatible = "st,spear600-fsmc-nand";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = <0xd1800000 0x1000 /* FSMC Register */
+ 0xd2000000 0x4000>; /* NAND Base */
+ reg-names = "fsmc_regs", "nand_data";
+ st,ale-off = <0x20000>;
+ st,cle-off = <0x10000>;
+
+ bank-width = <1>;
+ nand-skip-bbtscan;
+
+ partition at 0 {
+ ...
+ };
+ };
diff --git a/drivers/mtd/nand/fsmc_nand.c b/drivers/mtd/nand/fsmc_nand.c
index 0490182..1b8330e 100644
--- a/drivers/mtd/nand/fsmc_nand.c
+++ b/drivers/mtd/nand/fsmc_nand.c
@@ -31,6 +31,7 @@
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/platform_device.h>
+#include <linux/of.h>
#include <linux/mtd/partitions.h>
#include <linux/io.h>
#include <linux/slab.h>
@@ -854,6 +855,38 @@ static bool filter(struct dma_chan *chan, void *slave)
return true;
}
+#ifdef CONFIG_OF
+static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
+ struct device_node *np)
+{
+ struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ u32 val;
+
+ /* Set default NAND width to 8 bits */
+ pdata->width = 8;
+ if (!of_property_read_u32(np, "bank-width", &val)) {
+ if (val == 2) {
+ pdata->width = 16;
+ } else if (val != 1) {
+ dev_err(&pdev->dev, "invalid bank-width %u\n", val);
+ return -EINVAL;
+ }
+ }
+ of_property_read_u32(np, "st,ale-off", &pdata->ale_off);
+ of_property_read_u32(np, "st,cle-off", &pdata->cle_off);
+ if (of_get_property(np, "nand-skip-bbtscan", NULL))
+ pdata->options = NAND_SKIP_BBTSCAN;
+
+ return 0;
+}
+#else
+static int __devinit fsmc_nand_probe_config_dt(struct platform_device *pdev,
+ struct device_node *np)
+{
+ return -ENOSYS;
+}
+#endif
+
/*
* fsmc_nand_probe - Probe function
* @pdev: platform device structure
@@ -861,6 +894,8 @@ static bool filter(struct dma_chan *chan, void *slave)
static int __init fsmc_nand_probe(struct platform_device *pdev)
{
struct fsmc_nand_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct device_node __maybe_unused *np = pdev->dev.of_node;
+ struct mtd_part_parser_data ppdata = {};
struct fsmc_nand_data *host;
struct mtd_info *mtd;
struct nand_chip *nand;
@@ -870,6 +905,16 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
u32 pid;
int i;
+ if (np) {
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ pdev->dev.platform_data = pdata;
+ ret = fsmc_nand_probe_config_dt(pdev, np);
+ if (ret) {
+ dev_err(&pdev->dev, "no platform data\n");
+ return -ENODEV;
+ }
+ }
+
if (!pdata) {
dev_err(&pdev->dev, "platform data is NULL\n");
return -EINVAL;
@@ -1113,7 +1158,8 @@ static int __init fsmc_nand_probe(struct platform_device *pdev)
* Check for partition info passed
*/
host->mtd.name = "nand";
- ret = mtd_device_parse_register(&host->mtd, NULL, NULL,
+ ppdata.of_node = np;
+ ret = mtd_device_parse_register(&host->mtd, NULL, &ppdata,
host->partitions, host->nr_partitions);
if (ret)
goto err_probe;
@@ -1183,11 +1229,20 @@ static int fsmc_nand_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
#endif
+#ifdef CONFIG_OF
+static const struct of_device_id fsmc_nand_id_table[] = {
+ { .compatible = "st,spear600-fsmc-nand" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
+#endif
+
static struct platform_driver fsmc_nand_driver = {
.remove = fsmc_nand_remove,
.driver = {
.owner = THIS_MODULE,
.name = "fsmc-nand",
+ .of_match_table = of_match_ptr(fsmc_nand_id_table),
#ifdef CONFIG_PM
.pm = &fsmc_nand_pm_ops,
#endif
diff --git a/include/linux/mtd/fsmc.h b/include/linux/mtd/fsmc.h
index 823359c..b200292 100644
--- a/include/linux/mtd/fsmc.h
+++ b/include/linux/mtd/fsmc.h
@@ -156,8 +156,8 @@ struct fsmc_nand_platform_data {
unsigned int bank;
/* CLE, ALE offsets */
- unsigned long cle_off;
- unsigned long ale_off;
+ unsigned int cle_off;
+ unsigned int ale_off;
enum access_mode mode;
void (*select_bank)(uint32_t bank, uint32_t busw);
--
1.7.9.2
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