From 032c84381751bab0fe1da2e963af41cbe52c303d Mon Sep 17 00:00:00 2001 From: David Hendricks Date: Fri, 11 Apr 2014 19:48:55 -0700 Subject: spi_flash: Move (de-)assertion of /CS to single location This consolidates all calls to spi_claim_bus() and spi_release_bus() to a single location where spi_xfer() is called. This avoids confusing (and potentially redundant) calls that were being done throughout the generic spi_flash.c functions and chip-specific functions. I don't think the current approach could even work since many chip drivers assert /CS once and then issue multiple commands such as page program followed by reading the status register. I suspect the reason we didn't notice it on x86 is because the ICH/PCH handled each individual command correctly (spi_claim_bus() and spi_release_bus() are noops) in spite of the broken code. BUG=none BRANCH=none TEST=tested on nyan and link Signed-off-by: David Hendricks Original-Change-Id: I3257e2f6a2820834f4c9018069f90fcf2bab05f6 Original-Reviewed-on: https://chromium-review.googlesource.com/194510 Original-Reviewed-by: David Hendricks Original-Commit-Queue: David Hendricks Original-Tested-by: David Hendricks (cherry picked from commit d3394d34fb49e9e252f67371674d5b3aa220bc9e) Signed-off-by: Marc Jones Change-Id: Ieb62309b18090d8f974f91a6e448af3d65dd3d1d Reviewed-on: http://review.coreboot.org/7829 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer --- src/drivers/spi/spi_flash.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) (limited to 'src/drivers/spi/spi_flash.c') diff --git a/src/drivers/spi/spi_flash.c b/src/drivers/spi/spi_flash.c index 0d67c43385..d737ee9e61 100644 --- a/src/drivers/spi/spi_flash.c +++ b/src/drivers/spi/spi_flash.c @@ -46,6 +46,9 @@ static int do_spi_flash_cmd(struct spi_slave *spi, const void *dout, { int ret = 1; + if (spi_claim_bus(spi)) + return ret; + #if CONFIG_SPI_ATOMIC_SEQUENCING == 1 if (spi_xfer(spi, dout, bytes_out, din, bytes_in) < 0) goto done; @@ -63,6 +66,7 @@ static int do_spi_flash_cmd(struct spi_slave *spi, const void *dout, ret = 0; done: + spi_release_bus(spi); return ret; } @@ -111,9 +115,7 @@ int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd, int ret; spi->rw = SPI_READ_FLAG; - spi_claim_bus(spi); ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len); - spi_release_bus(spi); return ret; } @@ -188,11 +190,6 @@ int spi_flash_cmd_erase(struct spi_flash *flash, u8 erase_cmd, } flash->spi->rw = SPI_WRITE_FLAG; - ret = spi_claim_bus(flash->spi); - if (ret) { - printk(BIOS_WARNING, "SF: Unable to claim SPI bus\n"); - return ret; - } cmd[0] = erase_cmd; start = offset; @@ -222,7 +219,6 @@ int spi_flash_cmd_erase(struct spi_flash *flash, u8 erase_cmd, printk(BIOS_DEBUG, "SF: Successfully erased %zu bytes @ %#x\n", len, start); out: - spi_release_bus(flash->spi); return ret; } @@ -307,11 +303,6 @@ struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs) } spi->rw = SPI_READ_FLAG; - ret = spi_claim_bus(spi); - if (ret) { - printk(BIOS_WARNING, "SF: Failed to claim SPI bus: %d\n", ret); - goto err_claim_bus; - } if (spi->force_programmer_specific && spi->programmer_specific_probe) { flash = spi->programmer_specific_probe (spi); @@ -375,13 +366,9 @@ flash_detected: printk(BIOS_INFO, "SF: Detected %s with page size %x, total %x\n", flash->name, flash->sector_size, flash->size); - spi_release_bus(spi); - return flash; err_manufacturer_probe: err_read_id: - spi_release_bus(spi); -err_claim_bus: return NULL; } -- cgit v1.2.3