[PATCH] mtd: nand: fsmc: update of OF support
Linus Walleij
linus.walleij at stericsson.com
Mon Apr 29 08:07:48 EDT 2013
From: Mian Yousaf Kaukab <mian.yousaf.kaukab at stericsson.com>
Add nand bank selection and timings to the device tree bindings.
Cc: Stefan Roese <sr at denx.de>
Cc: Vipin Kumar <vipin.kumar at st.com>
Signed-off-by: Mian Yousaf Kaukab <mian.yousaf.kaukab at stericsson.com>
[Added some documentation]
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
.../devicetree/bindings/mtd/fsmc-nand.txt | 25 +++++++++++++++++++++-
drivers/mtd/nand/fsmc_nand.c | 18 ++++++++++++++++
include/linux/mtd/fsmc.h | 1 +
3 files changed, 43 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
index 2240ac0..ec42935 100644
--- a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
@@ -1,4 +1,5 @@
-* FSMC NAND
+ST Microelectronics Flexible Static Memory Controller (FSMC)
+NAND Interface
Required properties:
- compatible : "st,spear600-fsmc-nand", "stericsson,fsmc-nand"
@@ -9,6 +10,26 @@ 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
+- timings: array of 6 bytes for NAND timings. The meanings of these bytes
+ are:
+ byte 0 TCLR : CLE to RE delay in number of AHB clock cycles, only 4 bits
+ are valid. Zero means one clockcycle, 15 means 16 clock
+ cycles.
+ byte 1 TAR : ALE to RE delay, 4 bits are valid. Same format as TCLR.
+ byte 2 THIZ : number of HCLK clock cycles during which the data bus is
+ kept in Hi-Z (tristate) after the start of a write access.
+ Only valid for write transactions. Zero means zero cycles,
+ 255 means 255 cycles.
+ byte 3 THOLD : number of HCLK clock cycles to hold the address (and data
+ when writing) after the command deassertation. Zero means
+ one cycle, 255 means 256 cycles.
+ byte 4 TWAIT : number of HCLK clock cycles to assert the command to the
+ NAND flash in response to SMWAITn. Zero means 1 cycle,
+ 255 means 256 cycles.
+ byte 5 TSET : number of HCLK clock cycles to assert the address before the
+ command is asserted. Zero means one cycle, 255 means 256
+ cycles.
+- bank: default NAND bank to use (0-3 are valid, 0 is the default).
Example:
@@ -24,6 +45,8 @@ Example:
bank-width = <1>;
nand-skip-bbtscan;
+ timings = /bits/ 8 <0 0 0 2 3 0>;
+ bank = <1>;
partition at 0 {
...
diff --git a/drivers/mtd/nand/fsmc_nand.c b/drivers/mtd/nand/fsmc_nand.c
index 05ba3f0..a4ca95c 100644
--- a/drivers/mtd/nand/fsmc_nand.c
+++ b/drivers/mtd/nand/fsmc_nand.c
@@ -889,6 +889,24 @@ static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
if (of_get_property(np, "nand-skip-bbtscan", NULL))
pdata->options = NAND_SKIP_BBTSCAN;
+ pdata->nand_timings = devm_kzalloc(&pdev->dev,
+ sizeof(*pdata->nand_timings), GFP_KERNEL);
+ if (!pdata->nand_timings) {
+ dev_err(&pdev->dev, "no memory for nand_timing\n");
+ return -ENOMEM;
+ }
+ of_property_read_u8_array(np, "timings", (u8 *)pdata->nand_timings,
+ sizeof(*pdata->nand_timings));
+
+ /* Set default NAND bank to 0 */
+ pdata->bank = 0;
+ if (!of_property_read_u32(np, "bank", &val)) {
+ if (val > 3) {
+ dev_err(&pdev->dev, "invalid bank %u\n", val);
+ return -EINVAL;
+ }
+ pdata->bank = val;
+ }
return 0;
}
#else
diff --git a/include/linux/mtd/fsmc.h b/include/linux/mtd/fsmc.h
index d6ed61e..c8be32e 100644
--- a/include/linux/mtd/fsmc.h
+++ b/include/linux/mtd/fsmc.h
@@ -137,6 +137,7 @@ enum access_mode {
/**
* fsmc_nand_platform_data - platform specific NAND controller config
+ * @nand_timings: timing setup for the physical NAND interface
* @partitions: partition table for the platform, use a default fallback
* if this is NULL
* @nr_partitions: the number of partitions in the previous entry
--
1.7.11.3
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