From fa0d2f44aa6879e21843d517138510ccb7e1e39f Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Mon, 12 Aug 2019 13:09:04 -0700 Subject: [PATCH] watchdog: ziirave_wdt: Fix DOWNLOAD_START payload Bootloader firmware expects the following traffic for DOWNLOAD_END: S Addr Wr [A] 0x10 [A] P using ziirave_firm_write_byte() will result in S Addr Wr [A] 0x10 [A] 0x01 [A] 0x01 [A] P which happens to work because firmware will ignore any extra bytes sent. Fix this by converting the code to use i2c_smbus_write_byte() instead. Signed-off-by: Andrey Smirnov Cc: Chris Healy Cc: Guenter Roeck Cc: Rick Ramstetter Cc: linux-watchdog@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20190812200906.31344-21-andrew.smirnov@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/ziirave_wdt.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/watchdog/ziirave_wdt.c b/drivers/watchdog/ziirave_wdt.c index 681f65349779..ed69fa82e09c 100644 --- a/drivers/watchdog/ziirave_wdt.c +++ b/drivers/watchdog/ziirave_wdt.c @@ -217,13 +217,6 @@ static int ziirave_firm_write_block_data(struct watchdog_device *wdd, return ret; } -static int ziirave_firm_write_byte(struct watchdog_device *wdd, u8 command, - u8 byte, bool wait_for_ack) -{ - return ziirave_firm_write_block_data(wdd, command, 1, &byte, - wait_for_ack); -} - static bool ziirave_firm_addr_readonly(u32 addr) { return addr < ZIIRAVE_FIRM_FLASH_MEMORY_START || @@ -375,12 +368,18 @@ static int ziirave_firm_upload(struct watchdog_device *wdd, msleep(500); - ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_DOWNLOAD_START, 1, true); + ret = i2c_smbus_write_byte(client, ZIIRAVE_CMD_DOWNLOAD_START); if (ret) { dev_err(&client->dev, "Failed to start download\n"); return ret; } + ret = ziirave_firm_read_ack(wdd); + if (ret) { + dev_err(&client->dev, "No ACK for start download\n"); + return ret; + } + msleep(500); for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {