Update RPI 4.19 patches

root/target/linux/brcm2708/patches-4.19/0501-w1-fix-the-resume-command-API.patch

@@ -0,0 +1,50 @@
+From afb1d05657278c16cca2a9fa96ef9a6c7170d07d Mon Sep 17 00:00:00 2001
+From: Mariusz Bialonczyk <manio@skyboo.net>
+Date: Thu, 21 Mar 2019 11:52:55 +0100
+Subject: [PATCH 501/515] w1: fix the resume command API
+
+commit 62909da8aca048ecf9fbd7e484e5100608f40a63 upstream.
+
+>From the DS2408 datasheet [1]:
+"Resume Command function checks the status of the RC flag and, if it is set,
+ directly transfers control to the control functions, similar to a Skip ROM
+ command. The only way to set the RC flag is through successfully executing
+ the Match ROM, Search ROM, Conditional Search ROM, or Overdrive-Match ROM
+ command"
+
+The function currently works perfectly fine in a multidrop bus, but when we
+have only a single slave connected, then only a Skip ROM is used and Match
+ROM is not called at all. This is leading to problems e.g. with single one
+DS2408 connected, as the Resume Command is not working properly and the
+device is responding with failing results after the Resume Command.
+
+This commit is fixing this by using a Skip ROM instead in those cases.
+The bandwidth / performance advantage is exactly the same.
+
+Refs:
+[1] https://datasheets.maximintegrated.com/en/ds/DS2408.pdf
+
+Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
+Reviewed-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/w1/w1_io.c | 3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
+index 0364d3329c52..3516ce6718d9 100644
+--- a/drivers/w1/w1_io.c
++++ b/drivers/w1/w1_io.c
+@@ -432,8 +432,7 @@ int w1_reset_resume_command(struct w1_master *dev)
+ 	if (w1_reset_bus(dev))
+ 		return -1;
+ 
+-	/* This will make only the last matched slave perform a skip ROM. */
+-	w1_write_8(dev, W1_RESUME_CMD);
++	w1_write_8(dev, dev->slave_count > 1 ? W1_RESUME_CMD : W1_SKIP_ROM);
+ 	return 0;
+ }
+ EXPORT_SYMBOL_GPL(w1_reset_resume_command);
+-- 
+2.19.1
+