Adapt driver to do a memory mapped read.
Signed-off-by: Sourav Poddar <[email protected]>
---
v1->v2:
- Add a check to Wait for the previous erase/write to
finish.
- Ensure proper locking
drivers/mtd/devices/m25p80.c | 20 ++++++++++++++++++++
1 files changed, 20 insertions(+), 0 deletions(-)
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index b90c7e5..eb75d84 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -109,6 +109,7 @@ struct m25p {
u8 program_opcode;
u8 *command;
enum read_type flash_read;
+ void __iomem *mem_addr;
};
static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
@@ -515,6 +516,7 @@ 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);
+ struct spi_master *master = flash->spi->master;
struct spi_transfer t[2];
struct spi_message m;
uint8_t opcode;
@@ -523,6 +525,20 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from,
size_t len,
pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
__func__, (u32)from, len);
+ if (master->mmap) {
+ mutex_lock(&flash->lock);
+ /* Wait till previous write/erase is done. */
+ if (wait_till_ready(flash)) {
+ mutex_unlock(&flash->lock);
+ return 1;
+ }
+ flash->mem_addr = master->get_buf(master);
+ memcpy(buf, flash->mem_addr + from, len);
+ master->put_buf(master);
+ *retlen = len;
+ goto out;
+ }
+
spi_message_init(&m);
memset(t, 0, (sizeof t));
@@ -558,6 +574,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from,
size_t len,
*retlen = m.actual_length - m25p_cmdsz(flash) - dummy;
+out:
mutex_unlock(&flash->lock);
return 0;
@@ -1286,6 +1303,9 @@ static int m25p_probe(struct spi_device *spi)
flash->addr_width = 3;
}
+ if (spi->master->configure_from_slave)
+ m25p80_fill_flash_information(flash);
+
dev_info(&spi->dev, "%s (%lld Kbytes)\n", id->name,
(long long)flash->mtd.size >> 10);
--
1.7.1
--
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