From: Lucas Denefle Date: Wed, 23 Feb 2022 11:35:55 +0000 (+0000) Subject: w1: w1_therm: fixes w1_seq for ds28ea00 sensors X-Git-Tag: v4.19.238~50 X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=789988e2f2b1d7d1a4fd6f820917016484dbf558;p=wrapfs-3.14.y.git w1: w1_therm: fixes w1_seq for ds28ea00 sensors [ Upstream commit 41a92a89eee819298f805c40187ad8b02bb53426 ] w1_seq was failing due to several devices responding to the CHAIN_DONE at the same time. Now properly selects the current device in the chain with MATCH_ROM. Also acknowledgment was read twice. Signed-off-by: Lucas Denefle Link: https://lore.kernel.org/r/20220223113558.232750-1-lucas.denefle@converge.io Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c index 3c350dfbcd0b..aba727294bc8 100644 --- a/drivers/w1/slaves/w1_therm.c +++ b/drivers/w1/slaves/w1_therm.c @@ -693,16 +693,20 @@ static ssize_t w1_seq_show(struct device *device, if (sl->reg_num.id == reg_num->id) seq = i; + if (w1_reset_bus(sl->master)) + goto error; + + /* Put the device into chain DONE state */ + w1_write_8(sl->master, W1_MATCH_ROM); + w1_write_block(sl->master, (u8 *)&rn, 8); w1_write_8(sl->master, W1_42_CHAIN); w1_write_8(sl->master, W1_42_CHAIN_DONE); w1_write_8(sl->master, W1_42_CHAIN_DONE_INV); - w1_read_block(sl->master, &ack, sizeof(ack)); /* check for acknowledgment */ ack = w1_read_8(sl->master); if (ack != W1_42_SUCCESS_CONFIRM_BYTE) goto error; - } /* Exit from CHAIN state */