From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Drake Subject: [PATCH v2] i2c-pxa: prepare clock before use Date: Mon, 17 Jun 2013 11:30:36 -0400 (EDT) Message-ID: <20130617153036.67CC84375@dev.laptop.org> Return-path: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org On OLPC XO-1.75 (MMP2), a WARN_ON() was occurring during boot since the clock being enabled by i2c-pxa had not been prepared. Use clk_prepare_enable() to ensure that the prepare operation has taken place, and use clk_disable_unprepare() in the matching shutdown paths. Signed-off-by: Daniel Drake --- drivers/i2c/busses/i2c-pxa.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) v2: add the "other half" - thanks Wolfram! diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index ea6d45d..fbafed2 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -1160,7 +1160,7 @@ static int i2c_pxa_probe(struct platform_device *dev) i2c->adap.class = plat->class; } - clk_enable(i2c->clk); + clk_prepare_enable(i2c->clk); if (i2c->use_pio) { i2c->adap.algo = &i2c_pxa_pio_algorithm; @@ -1202,7 +1202,7 @@ eadapt: if (!i2c->use_pio) free_irq(irq, i2c); ereqirq: - clk_disable(i2c->clk); + clk_disable_unprepare(i2c->clk); iounmap(i2c->reg_base); eremap: clk_put(i2c->clk); @@ -1221,7 +1221,7 @@ static int i2c_pxa_remove(struct platform_device *dev) if (!i2c->use_pio) free_irq(i2c->irq, i2c); - clk_disable(i2c->clk); + clk_disable_unprepare(i2c->clk); clk_put(i2c->clk); iounmap(i2c->reg_base); -- 1.8.1.4