| Message ID | 1369389564-13181-2-git-send-email-b32955@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 24, 2013 at 05:59:19PM +0800, Huang Shijie wrote: > +Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM: > + > + weim: weim@021b8000 { > + compatible = "fsl,imx6q-weim"; > + reg = <0x021b8000 0x4000>; > + clocks = <&clks 196>; > + #address-cells = <2>; > + #size-cells = <1>; > + ranges = <0 0 0x08000000 0x08000000>; > + > + nor@0,0 { > + compatible = "cfi-flash"; > + reg = <0 0 0x02000000>; > + #address-cells = <1>; > + #size-cells = <1>; > + bank-width = <2>; > + Nit: remove this unneeded blank line. > + fsl,weim-cs-timing = <0x00620081 0x00000001 0x1C022000 > + 0x0000C000 0x1404a38e 0x00000000>; Nit: please consistently use lower case for hex value. Please update patch #6 as well. Other than that, Reviewed-by: Shawn Guo <shawn.guo@linaro.org> > + }; > + };
On Fri, May 24, 2013 at 05:59:19PM +0800, Huang Shijie wrote: > The WEIM(Wireless External Interface Module) works like a bus. > You can attach many different devices on it, such as NOR, onenand. > > In the case of i.MX6q-sabreauto, the NOR is connected to WEIM. > > This patch also adds the devicetree binding document. > The driver only works when the devicetree is enabled. > > Signed-off-by: Huang Shijie <b32955@freescale.com> > --- > Documentation/devicetree/bindings/bus/imx-weim.txt | 50 +++++++ > drivers/bus/Kconfig | 9 ++ > drivers/bus/Makefile | 1 + > drivers/bus/imx-weim.c | 139 ++++++++++++++++++++ > 4 files changed, 199 insertions(+), 0 deletions(-) > create mode 100644 Documentation/devicetree/bindings/bus/imx-weim.txt > create mode 100644 drivers/bus/imx-weim.c > > diff --git a/Documentation/devicetree/bindings/bus/imx-weim.txt b/Documentation/devicetree/bindings/bus/imx-weim.txt > new file mode 100644 > index 0000000..e7a2950 > --- /dev/null > +++ b/Documentation/devicetree/bindings/bus/imx-weim.txt > @@ -0,0 +1,50 @@ > +Device tree bindings for i.MX Wireless External Interface Module (WEIM) > + > +The term "wireless" does not imply that the WEIM is literally an interface > +without wires. It simply means that this module was originally designed for > +wireless and mobile applications that use low-power technology. > + > +The actual devices are instantiated from the child nodes of a WEIM node. > + > +Required properties: > + > + - compatible: Should be set to "fsl,imx6q-weim" > + - reg: A resource specifier for the register space > + (see the example below) > + - clocks: the clock, see the example below. > + - #address-cells: Must be set to 2 to allow memory address translation > + - #size-cells: Must be set to 1 to allow CS address passing > + - ranges: Must be set up to reflect the memory layout with four > + integer values for each chip-select line in use: > + > + <cs-number> 0 <physical address of mapping> <size> > + > +Timing property for child nodes. It is mandatory, not optional. > + > + - fsl,weim-cs-timing: The timing array, contains 6 timing values for the > + child node. We can get the CS index from the child > + node's "reg" property. This property contains the values > + for the registers EIM_CSnGCR1, EIM_CSnGCR2, EIM_CSnRCR1, > + EIM_CSnRCR2, EIM_CSnWCR1, EIM_CSnWCR2 in this order. > + > +Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM: > + > + weim: weim@021b8000 { > + compatible = "fsl,imx6q-weim"; > + reg = <0x021b8000 0x4000>; > + clocks = <&clks 196>; > + #address-cells = <2>; > + #size-cells = <1>; > + ranges = <0 0 0x08000000 0x08000000>; > + > + nor@0,0 { > + compatible = "cfi-flash"; > + reg = <0 0 0x02000000>; > + #address-cells = <1>; > + #size-cells = <1>; > + bank-width = <2>; > + > + fsl,weim-cs-timing = <0x00620081 0x00000001 0x1C022000 > + 0x0000C000 0x1404a38e 0x00000000>; > + }; > + }; > diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig > index b05ecab..46cd5bb 100644 > --- a/drivers/bus/Kconfig > +++ b/drivers/bus/Kconfig > @@ -4,6 +4,15 @@ > > menu "Bus devices" > > +config IMX_WEIM > + bool "Freescale EIM DRIVER" > + depends on ARCH_MXC > + help > + Driver for i.MX6 WEIM controller. > + The WEIM(Wireless External Interface Module) works like a bus. > + You can attach many different devices on it, such as NOR, onenand. > + But now, we only support the Parallel NOR. > + > config MVEBU_MBUS > bool > depends on PLAT_ORION > diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile > index 3c7b53c..436bbcc 100644 > --- a/drivers/bus/Makefile > +++ b/drivers/bus/Makefile > @@ -2,6 +2,7 @@ > # Makefile for the bus drivers. > # > > +obj-$(CONFIG_IMX_WEIM) += imx-weim.o > obj-$(CONFIG_MVEBU_MBUS) += mvebu-mbus.o > obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o > > diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c > new file mode 100644 > index 0000000..aef865d > --- /dev/null > +++ b/drivers/bus/imx-weim.c > @@ -0,0 +1,139 @@ > +/* > + * EIM driver for Freescale's i.MX chips > + * > + * Copyright (C) 2013 Freescale Semiconductor, Inc. > + * > + * This file is licensed under the terms of the GNU General Public > + * License version 2. This program is licensed "as is" without any > + * warranty of any kind, whether express or implied. > + */ > +#include <linux/module.h> > +#include <linux/clk.h> > +#include <linux/io.h> > +#include <linux/of_device.h> > + > +struct imx_weim { > + void __iomem *base; > + struct clk *clk; > +}; > + > +static const struct of_device_id weim_id_table[] = { > + { .compatible = "fsl,imx6q-weim", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, weim_id_table); > + > +#define CS_TIMING_LEN 6 > +#define CS_REG_RANGE 0x18 > + > +/* Parse and set the timing for this device. */ > +static int > +weim_timing_setup(struct platform_device *pdev, struct device_node *np) > +{ > + struct imx_weim *weim = platform_get_drvdata(pdev); > + u32 value[CS_TIMING_LEN]; > + u32 cs_idx; > + int ret; > + int i; > + > + /* get the CS index from this child node's "reg" property. */ > + ret = of_property_read_u32(np, "reg", &cs_idx); > + if (ret) > + return ret; > + > + /* The weim has four chip selects. */ > + if (cs_idx > 3) > + return -EINVAL; > + > + ret = of_property_read_u32_array(np, "fsl,weim-cs-timing", > + value, CS_TIMING_LEN); > + if (ret) > + return ret; > + > + /* set the timing for WEIM */ > + for (i = 0; i < CS_TIMING_LEN; i++) > + writel(value[i], weim->base + cs_idx * CS_REG_RANGE + i * 4); > + return 0; > +} > + > +static void weim_parse_dt(struct platform_device *pdev) > +{ > + struct device_node *child; > + > + for_each_child_of_node(pdev->dev.of_node, child) { > + if (!child->name) > + continue; > + > + if (weim_timing_setup(pdev, child)) { > + dev_err(&pdev->dev, "%s set timing failed.\n", > + child->full_name); > + continue; > + } Since you know use of_platform_populate you can't skip erroneous devices anymore, so you have to bail out. > + } > + > + if (of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev) < 0) > + dev_err(&pdev->dev, "%s fail to create devices.\n", > + pdev->dev.of_node->full_name); > +} > + > +static int weim_probe(struct platform_device *pdev) > +{ > + struct imx_weim *weim; > + struct resource *res; > + int ret = -EINVAL; > + > + weim = devm_kzalloc(&pdev->dev, sizeof(*weim), GFP_KERNEL); > + if (!weim) { > + ret = -ENOMEM; > + goto weim_err; > + } > + platform_set_drvdata(pdev, weim); > + > + /* get the resource */ > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + weim->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(weim->base)) { > + ret = PTR_ERR(weim->base); > + goto weim_err; > + } > + > + /* get the clock */ > + weim->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(weim->clk)) > + goto weim_err; > + > + ret = clk_prepare_enable(weim->clk); > + if (ret) > + goto weim_err; > + > + /* parse the device node */ > + weim_parse_dt(pdev); > + > + dev_info(&pdev->dev, "WEIM driver registered.\n"); > + return 0; > + > +weim_err: > + return ret; > +} > + > +static int weim_remove(struct platform_device *pdev) > +{ > + struct imx_weim *weim = platform_get_drvdata(pdev); > + > + clk_disable_unprepare(weim->clk); I'm running out of ideas how to explain this. Just drop this remove function. You do not allow building this as module. If you did, then your first job here would be to unregister your child devices. Then afterwards you could disable the clock. If you just disable the clock without unregistering your children then all you do is to make the child devices nonfuntional. Sascha
? 2013?05?27? 15:44, Sascha Hauer ??: > I'm running out of ideas how to explain this. Just drop this remove > function. You do not allow building this as module. If you did, then ok. thanks Huang Shijie
diff --git a/Documentation/devicetree/bindings/bus/imx-weim.txt b/Documentation/devicetree/bindings/bus/imx-weim.txt new file mode 100644 index 0000000..e7a2950 --- /dev/null +++ b/Documentation/devicetree/bindings/bus/imx-weim.txt @@ -0,0 +1,50 @@ +Device tree bindings for i.MX Wireless External Interface Module (WEIM) + +The term "wireless" does not imply that the WEIM is literally an interface +without wires. It simply means that this module was originally designed for +wireless and mobile applications that use low-power technology. + +The actual devices are instantiated from the child nodes of a WEIM node. + +Required properties: + + - compatible: Should be set to "fsl,imx6q-weim" + - reg: A resource specifier for the register space + (see the example below) + - clocks: the clock, see the example below. + - #address-cells: Must be set to 2 to allow memory address translation + - #size-cells: Must be set to 1 to allow CS address passing + - ranges: Must be set up to reflect the memory layout with four + integer values for each chip-select line in use: + + <cs-number> 0 <physical address of mapping> <size> + +Timing property for child nodes. It is mandatory, not optional. + + - fsl,weim-cs-timing: The timing array, contains 6 timing values for the + child node. We can get the CS index from the child + node's "reg" property. This property contains the values + for the registers EIM_CSnGCR1, EIM_CSnGCR2, EIM_CSnRCR1, + EIM_CSnRCR2, EIM_CSnWCR1, EIM_CSnWCR2 in this order. + +Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM: + + weim: weim@021b8000 { + compatible = "fsl,imx6q-weim"; + reg = <0x021b8000 0x4000>; + clocks = <&clks 196>; + #address-cells = <2>; + #size-cells = <1>; + ranges = <0 0 0x08000000 0x08000000>; + + nor@0,0 { + compatible = "cfi-flash"; + reg = <0 0 0x02000000>; + #address-cells = <1>; + #size-cells = <1>; + bank-width = <2>; + + fsl,weim-cs-timing = <0x00620081 0x00000001 0x1C022000 + 0x0000C000 0x1404a38e 0x00000000>; + }; + }; diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index b05ecab..46cd5bb 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -4,6 +4,15 @@ menu "Bus devices" +config IMX_WEIM + bool "Freescale EIM DRIVER" + depends on ARCH_MXC + help + Driver for i.MX6 WEIM controller. + The WEIM(Wireless External Interface Module) works like a bus. + You can attach many different devices on it, such as NOR, onenand. + But now, we only support the Parallel NOR. + config MVEBU_MBUS bool depends on PLAT_ORION diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile index 3c7b53c..436bbcc 100644 --- a/drivers/bus/Makefile +++ b/drivers/bus/Makefile @@ -2,6 +2,7 @@ # Makefile for the bus drivers. # +obj-$(CONFIG_IMX_WEIM) += imx-weim.o obj-$(CONFIG_MVEBU_MBUS) += mvebu-mbus.o obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c new file mode 100644 index 0000000..aef865d --- /dev/null +++ b/drivers/bus/imx-weim.c @@ -0,0 +1,139 @@ +/* + * EIM driver for Freescale's i.MX chips + * + * Copyright (C) 2013 Freescale Semiconductor, Inc. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ +#include <linux/module.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/of_device.h> + +struct imx_weim { + void __iomem *base; + struct clk *clk; +}; + +static const struct of_device_id weim_id_table[] = { + { .compatible = "fsl,imx6q-weim", }, + {} +}; +MODULE_DEVICE_TABLE(of, weim_id_table); + +#define CS_TIMING_LEN 6 +#define CS_REG_RANGE 0x18 + +/* Parse and set the timing for this device. */ +static int +weim_timing_setup(struct platform_device *pdev, struct device_node *np) +{ + struct imx_weim *weim = platform_get_drvdata(pdev); + u32 value[CS_TIMING_LEN]; + u32 cs_idx; + int ret; + int i; + + /* get the CS index from this child node's "reg" property. */ + ret = of_property_read_u32(np, "reg", &cs_idx); + if (ret) + return ret; + + /* The weim has four chip selects. */ + if (cs_idx > 3) + return -EINVAL; + + ret = of_property_read_u32_array(np, "fsl,weim-cs-timing", + value, CS_TIMING_LEN); + if (ret) + return ret; + + /* set the timing for WEIM */ + for (i = 0; i < CS_TIMING_LEN; i++) + writel(value[i], weim->base + cs_idx * CS_REG_RANGE + i * 4); + return 0; +} + +static void weim_parse_dt(struct platform_device *pdev) +{ + struct device_node *child; + + for_each_child_of_node(pdev->dev.of_node, child) { + if (!child->name) + continue; + + if (weim_timing_setup(pdev, child)) { + dev_err(&pdev->dev, "%s set timing failed.\n", + child->full_name); + continue; + } + } + + if (of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev) < 0) + dev_err(&pdev->dev, "%s fail to create devices.\n", + pdev->dev.of_node->full_name); +} + +static int weim_probe(struct platform_device *pdev) +{ + struct imx_weim *weim; + struct resource *res; + int ret = -EINVAL; + + weim = devm_kzalloc(&pdev->dev, sizeof(*weim), GFP_KERNEL); + if (!weim) { + ret = -ENOMEM; + goto weim_err; + } + platform_set_drvdata(pdev, weim); + + /* get the resource */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + weim->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(weim->base)) { + ret = PTR_ERR(weim->base); + goto weim_err; + } + + /* get the clock */ + weim->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(weim->clk)) + goto weim_err; + + ret = clk_prepare_enable(weim->clk); + if (ret) + goto weim_err; + + /* parse the device node */ + weim_parse_dt(pdev); + + dev_info(&pdev->dev, "WEIM driver registered.\n"); + return 0; + +weim_err: + return ret; +} + +static int weim_remove(struct platform_device *pdev) +{ + struct imx_weim *weim = platform_get_drvdata(pdev); + + clk_disable_unprepare(weim->clk); + return 0; +} + +static struct platform_driver weim_driver = { + .driver = { + .name = "imx-weim", + .of_match_table = weim_id_table, + }, + .probe = weim_probe, + .remove = weim_remove, +}; + +module_platform_driver(weim_driver); +MODULE_AUTHOR("Freescale Semiconductor Inc."); +MODULE_DESCRIPTION("i.MX EIM Controller Driver"); +MODULE_LICENSE("GPL");
The WEIM(Wireless External Interface Module) works like a bus. You can attach many different devices on it, such as NOR, onenand. In the case of i.MX6q-sabreauto, the NOR is connected to WEIM. This patch also adds the devicetree binding document. The driver only works when the devicetree is enabled. Signed-off-by: Huang Shijie <b32955@freescale.com> --- Documentation/devicetree/bindings/bus/imx-weim.txt | 50 +++++++ drivers/bus/Kconfig | 9 ++ drivers/bus/Makefile | 1 + drivers/bus/imx-weim.c | 139 ++++++++++++++++++++ 4 files changed, 199 insertions(+), 0 deletions(-) create mode 100644 Documentation/devicetree/bindings/bus/imx-weim.txt create mode 100644 drivers/bus/imx-weim.c