From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Glass Date: Sun, 29 Dec 2019 21:19:15 -0700 Subject: [PATCH 06/19] aspeed: ast2500: Read clock ofdata in the correct method In-Reply-To: <20191230041928.74874-1-sjg@chromium.org> References: <20191230041928.74874-1-sjg@chromium.org> Message-ID: <20191229211913.6.I9f208c8708d1b33625601d8034ef08e6305c09d5@changeid> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de At present the clock driver reads its ofdata in the probe() method. This is not correct although it is often harmless. However in this case it causes a problem, something like this: - ast_get_scu() is called (from somewhere) to get the SCI address - this probes the clock - first sets up ofdata (which does nothing at present) - DM marks clock device as active - DM calls pinctrl - pinctrl probes and calls ast_get_scu() in ast2500_pinctrl_probe() - ast_get_scu() probes the clock, but sees it already marked as probed - ast_get_scu() accesses the clock's private data, with scu as NULL - DM calls clock probe function ast2500_clk_probe() which reads scu By putting the read of scu into the correct method, scu is read as part of ofdata setup, and everything is OK. Note: This problem did not matter until now since DM always probed all parents before reading a child's ofdata. The fact that pinctrl is a child of clock seems to trigger this strange bug. Signed-off-by: Simon Glass --- drivers/clk/aspeed/clk_ast2500.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/clk/aspeed/clk_ast2500.c b/drivers/clk/aspeed/clk_ast2500.c index 9249cf9cdf..b3a3f3d4dd 100644 --- a/drivers/clk/aspeed/clk_ast2500.c +++ b/drivers/clk/aspeed/clk_ast2500.c @@ -490,7 +490,7 @@ struct clk_ops ast2500_clk_ops = { .enable = ast2500_clk_enable, }; -static int ast2500_clk_probe(struct udevice *dev) +static int ast2500_clk_ofdata_to_platdata(struct udevice *dev) { struct ast2500_clk_priv *priv = dev_get_priv(dev); @@ -525,5 +525,5 @@ U_BOOT_DRIVER(aspeed_ast2500_scu) = { .priv_auto_alloc_size = sizeof(struct ast2500_clk_priv), .ops = &ast2500_clk_ops, .bind = ast2500_clk_bind, - .probe = ast2500_clk_probe, + .ofdata_to_platdata = ast2500_clk_ofdata_to_platdata, }; -- 2.24.1.735.g03f4e72817-goog