From 5ea2a2ace5a0156e7c56d084a3306dc8f7015b8b Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Mon, 3 Jul 2017 21:28:23 +0200 Subject: [PATCH] mmc: tmio: fix CMD12 (STOP) handling MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit I always anticipated this code to be not correct, but now I had a test case to prove it. According to all documentation I have, setting the TMIO_STOP_STP bit ever only worked during block transfers. This bit is like manually enforcing an autocmd12 during a so far seamless transfer. It does NOT work when the block transfer had errors. It also does NOT work with any other cmd except block commands. For all those, CMD12 has to be treated like any other command. So, basically, we could use this bit only for mrq->data->stop cmds. But for these, we happily use the autocmd12 feature using the TMIO_STOP_SEC bit. As a result, the above bit is not useful for us and we need to treat CMD12 as a regular cmd always. Just remove the special handling code. Note that the BSP recognized this issue as well yet had a more cautious solution to the problem [1]. Which is understandable but makes CMD12 handling even more complicated. Checked with a Renesas Salvator-X/M3-W which needed to send CMD12 when retuning one of my SD cards. [1] https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas-bsp.git/commit/?id=2838a2ff8ca776f6d18b7fbbe75f3df8dd64183a Signed-off-by: Wolfram Sang Tested-by: Jan Klötzke Tested-by: Nguyen Viet Dung Signed-off-by: Ulf Hansson --- drivers/mmc/host/tmio_mmc_core.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c index db77973..ad31bdf 100644 --- a/drivers/mmc/host/tmio_mmc_core.c +++ b/drivers/mmc/host/tmio_mmc_core.c @@ -349,12 +349,6 @@ static int tmio_mmc_start_command(struct tmio_mmc_host *host, int c = cmd->opcode; u32 irq_mask = TMIO_MASK_CMD; - /* CMD12 is handled by hardware */ - if (cmd->opcode == MMC_STOP_TRANSMISSION && !cmd->arg) { - sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, TMIO_STOP_STP); - return 0; - } - switch (mmc_resp_type(cmd)) { case MMC_RSP_NONE: c |= RESP_NONE; break; case MMC_RSP_R1: -- 2.7.4