On Thu, Feb 13, 2014 at 11:38:25PM +0100, Philippe De Muyter wrote: > Hi Shawn, > > On Thu, Feb 13, 2014 at 08:59:02PM +0800, Shawn Guo wrote: > > For imx6q-weim type of device, there might a WEIM CS space configuration > > register in General Purpose Register controller, e.g. IOMUXC_GPR1 on > > i.MX6Q. > > > > Depending on which configuration of the following 4 is chosen for given > > system, IOMUXC_GPR1[11:0] should be set up as 05, 033, 0113 or 01111 > > correspondingly. > > > > CS0(128M) CS1(0M) CS2(0M) CS3(0M) > > CS0(64M) CS1(64M) CS2(0M) CS3(0M) > > CS0(64M) CS1(32M) CS2(32M) CS3(0M) > > CS0(32M) CS1(32M) CS2(32M) CS3(32M) > > > > The patch creates a function for imx6q-weim type of device, which scans > > 'ranges' property of WEIM node and build the GPR value incrementally. > > Thus the WEIM CS GPR can be set up automatically at boot time. > > Please add that text to Documentation/devicetree/bindings/bus/imx-weim.txt. Since the patch does not add any new device tree properties, I do not think we need to necessarily update bindings doc in this patch. I prefer to improve the doc with another separate patch. > > > > > Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx> > > --- > > Changes since v1: > > - Drop device tree property fsl,weim-cs-gpr > > - Use octal value for IOMUXC_GPR1[11:0] bit field > > - Use of_property_for_each_u32() to build gprval incrementally > > > > drivers/bus/imx-weim.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 59 insertions(+) > > > > diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c > > index 3ef58c8..a120c93 100644 > > --- a/drivers/bus/imx-weim.c > > +++ b/drivers/bus/imx-weim.c > > @@ -11,6 +11,9 @@ > > #include <linux/clk.h> > > #include <linux/io.h> > > #include <linux/of_device.h> > > +#include <linux/mfd/syscon.h> > > +#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h> > > +#include <linux/regmap.h> > > > > struct imx_weim_devtype { > > unsigned int cs_count; > > @@ -56,6 +59,59 @@ static const struct of_device_id weim_id_table[] = { > > }; > > MODULE_DEVICE_TABLE(of, weim_id_table); > > > > +static int __init imx6q_weim_gpr_setup(struct platform_device *pdev) > > +{ > > + struct device_node *np = pdev->dev.of_node; > > + struct property *prop; > > + const __be32 *p; > > + struct regmap *gpr; > > + u32 gprvals[4] = { > > + 05, /* CS0(128M) CS1(0M) CS2(0M) CS3(0M) */ > > + 033, /* CS0(64M) CS1(64M) CS2(0M) CS3(0M) */ > > + 0113, /* CS0(64M) CS1(32M) CS2(32M) CS3(0M) */ > > + 0111, /* CS0(64M) CS1(32M) CS2(32M) CS3(0M) */ > > 01111, /* CS0(32M) CS1(32M) CS2(32M) CS3(32M) */ Oops, thanks. > > > + }; > > + u32 gprval = 0; > > + u32 val; > > + int len; > > + int cs = 0; > > + int i = 0; > > + > > + gpr = syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr"); > > + if (IS_ERR(gpr)) { > > + dev_err(&pdev->dev, "failed to find fsl,imx6q-iomuxc-gpr\n"); > > + return -ENOENT; > > + } > > + > > + prop = of_find_property(np, "ranges", &len); > > + if (prop == NULL) > > + return -ENOENT; > > + if (len % (sizeof(u32) * 4)) > > + return -EINVAL; > > + > > + of_property_for_each_u32(np, "ranges", prop, p, val) { > > + if (i % 4 == 0) { > > + cs = val; > > + } else if (i % 4 == 3 && val) { > > + val /= SZ_64M; > > + val = (val << 1) | 1; > > or > val = (val / SZ_32M) | 1; Okay. > > > + gprval |= val << cs * 3; > > + } > > + i++; > > + } > > You may replace the tests above (from "prop = of_find_property" to "EINVAL;") > by : > if (i == 0 || (i % 4)) > goto err; Yeah, it's better. I will roll these changes into v3. > > + > > + for (i = 0; i < ARRAY_SIZE(gprvals); i++) { > > + if (gprval == gprvals[i]) { > > + /* Found it. Set up IOMUXC_GPR1[11:0] with it. */ > > + regmap_update_bits(gpr, IOMUXC_GPR1, 0xfff, gprval); > > + return 0; > > + } > > + } > > + > > err: > > > + dev_err(&pdev->dev, "Invalid 'ranges' configuration\n"); > > + return -EINVAL; > > +} > > + > > /* Parse and set the timing for this device. */ > > static int __init weim_timing_setup(struct device_node *np, void __iomem *base, > > const struct imx_weim_devtype *devtype) > > @@ -92,6 +148,9 @@ static int __init weim_parse_dt(struct platform_device *pdev, > > struct device_node *child; > > int ret; > > > > + if (of_device_is_compatible(pdev->dev.of_node, "fsl,imx6q-weim")) > > + imx6q_weim_gpr_setup(pdev); > > + > > for_each_child_of_node(pdev->dev.of_node, child) { > > if (!child->name) > > continue; > > -- > > 1.7.9.5 > > > > I have tested this v2 patch, and, except for the typo (0111 instead of 01111), > it works perfectly. Thanks for testing. Shawn -- 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