Hi, Kindly ping.. Any comments on this patch set? > -----Original Message----- > From: linux-kernel-owner@xxxxxxxxxxxxxxx [mailto:linux-kernel- > owner@xxxxxxxxxxxxxxx] On Behalf Of Peng Fan > Sent: Thursday, April 21, 2016 1:26 AM > To: shawnguo@xxxxxxxxxx; srinivas.kandagatla@xxxxxxxxxx; > maxime.ripard@xxxxxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; van.freenix@xxxxxxxxx > Subject: [PATCH V2 3/3] nvmem: imx-ocotp: handling clock > > Before access ocotp nvmem area, the clock should be enabled. > Or, `hexdump nvmem` will hang the system. So, use such flow: > " > 1. clock_enable_prepare > 2. read nvmem ocotp area > 3. clock_disable_unprepare > " > > Signed-off-by: Peng Fan <van.freenix@xxxxxxxxx> > Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> > Cc: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> > Cc: Shawn Guo <shawnguo@xxxxxxxxxx> > --- > > V2: > Follow Fabio's comments, check return value of clk_prepare_enable > > drivers/nvmem/imx-ocotp.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c index > d7796eb..3f1dd9f 100644 > --- a/drivers/nvmem/imx-ocotp.c > +++ b/drivers/nvmem/imx-ocotp.c > @@ -15,6 +15,7 @@ > * http://www.gnu.org/copyleft/gpl.html > */ > > +#include <linux/clk.h> > #include <linux/device.h> > #include <linux/io.h> > #include <linux/module.h> > @@ -27,6 +28,7 @@ > > struct ocotp_priv { > struct device *dev; > + struct clk *clk; > void __iomem *base; > unsigned int nregs; > }; > @@ -37,7 +39,7 @@ static int imx_ocotp_read(void *context, const void *reg, > size_t reg_size, > struct ocotp_priv *priv = context; > unsigned int offset = *(u32 *)reg; > unsigned int count; > - int i; > + int i, ret; > u32 index; > > index = offset >> 2; > @@ -46,11 +48,19 @@ static int imx_ocotp_read(void *context, const void > *reg, size_t reg_size, > if (count > (priv->nregs - index)) > count = priv->nregs - index; > > + ret = clk_prepare_enable(priv->clk); > + if (ret < 0) { > + dev_err(priv->dev, "failed to prepare/enable ocotp clk\n"); > + return ret; > + } > + > for (i = index; i < (index + count); i++) { > *(u32 *)val = readl(priv->base + 0x400 + i * 0x10); > val += 4; > } > > + clk_disable_unprepare(priv->clk); > + > return 0; > } > > @@ -112,6 +122,10 @@ static int imx_ocotp_probe(struct platform_device > *pdev) > if (IS_ERR(priv->base)) > return PTR_ERR(priv->base); > > + priv->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(priv->clk)) > + return PTR_ERR(priv->clk); > + > of_id = of_match_device(imx_ocotp_dt_ids, dev); > priv->nregs = (unsigned int)of_id->data; > imx_ocotp_regmap_config.max_register = 4 * priv->nregs - 4; > -- > 2.6.6 Thanks, Peng. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
