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Diffstat (limited to 'target/linux/brcm63xx/patches-3.6/203-MTD-DEVICES-m25p80-add-support-for-limiting-reads.patch')
-rw-r--r--target/linux/brcm63xx/patches-3.6/203-MTD-DEVICES-m25p80-add-support-for-limiting-reads.patch92
1 files changed, 92 insertions, 0 deletions
diff --git a/target/linux/brcm63xx/patches-3.6/203-MTD-DEVICES-m25p80-add-support-for-limiting-reads.patch b/target/linux/brcm63xx/patches-3.6/203-MTD-DEVICES-m25p80-add-support-for-limiting-reads.patch
new file mode 100644
index 0000000000..47eebba4c2
--- /dev/null
+++ b/target/linux/brcm63xx/patches-3.6/203-MTD-DEVICES-m25p80-add-support-for-limiting-reads.patch
@@ -0,0 +1,92 @@
+From 5fb4e8d7287ac8fcb33aae8b1e9e22c5a3c392bd Mon Sep 17 00:00:00 2001
+From: Jonas Gorski <jonas.gorski@gmail.com>
+Date: Thu, 10 Nov 2011 17:33:40 +0100
+Subject: [PATCH 51/79] MTD: DEVICES: m25p80: add support for limiting reads
+
+Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
+---
+ drivers/mtd/devices/m25p80.c | 29 +++++++++++++++++++++++++++--
+ include/linux/spi/flash.h | 4 ++++
+ 2 files changed, 31 insertions(+), 2 deletions(-)
+
+--- a/drivers/mtd/devices/m25p80.c
++++ b/drivers/mtd/devices/m25p80.c
+@@ -100,6 +100,7 @@ struct m25p {
+ u16 addr_width;
+ u8 erase_opcode;
+ u8 *command;
++ int max_transfer_len;
+ };
+
+ static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
+@@ -343,10 +344,9 @@ static int m25p80_erase(struct mtd_info
+ * Read an address range from the flash chip. The address range
+ * may be any size provided it is within the physical boundaries.
+ */
+-static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
++static int __m25p80_read(struct m25p *flash, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+ {
+- struct m25p *flash = mtd_to_m25p(mtd);
+ struct spi_transfer t[2];
+ struct spi_message m;
+
+@@ -395,6 +395,28 @@ static int m25p80_read(struct mtd_info *
+ return 0;
+ }
+
++static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
++ size_t *retlen, u_char *buf)
++{
++ struct m25p *flash = mtd_to_m25p(mtd);
++ size_t off;
++ size_t read_len = flash->max_transfer_len;
++ size_t part_len;
++ int ret = 0;
++
++ if (!read_len)
++ return __m25p80_read(flash, from, len, retlen, buf);
++
++ *retlen = 0;
++
++ for (off = 0; off < len && !ret; off += read_len) {
++ ret = __m25p80_read(flash, from + off, min(len - off, read_len),
++ &part_len, buf + off);
++ *retlen += part_len;
++ }
++
++ return ret;
++}
+ /*
+ * Write an address range to the flash chip. Data must be written in
+ * FLASH_PAGESIZE chunks. The address range may be any size provided
+@@ -871,6 +893,9 @@ static int __devinit m25p_probe(struct s
+ return -ENOMEM;
+ }
+
++ if (data)
++ flash->max_transfer_len = data->max_transfer_len;
++
+ flash->spi = spi;
+ mutex_init(&flash->lock);
+ dev_set_drvdata(&spi->dev, flash);
+--- a/include/linux/spi/flash.h
++++ b/include/linux/spi/flash.h
+@@ -13,6 +13,8 @@ struct mtd_part_parser_data;
+ * @part_probe_types: optional list of MTD parser names to use for
+ * partitioning
+ *
++ * @max_transfer_len: option maximum read/write length limitation for
++ * SPI controllers not able to transfer any length commands.
+ * Board init code (in arch/.../mach-xxx/board-yyy.c files) can
+ * provide information about SPI flash parts (such as DataFlash) to
+ * help set up the device and its appropriate default partitioning.
+@@ -28,6 +30,8 @@ struct flash_platform_data {
+ char *type;
+
+ const char **part_probe_types;
++
++ unsigned int max_transfer_len;
+ /* we'll likely add more ... use JEDEC IDs, etc */
+ };
+