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2016-03-28dm: i2c: mxc_i2c: implement i2c_idle_busPeng Fan
Implement i2c_idle_bus in driver, then setup_i2c can be dropped for boards which enable DM_I2C/DM_GPIO/PINCTRL. The i2c_idle_bus force bus idle flow follows setup_i2c in arch/arm/imx-common/i2c-mxv7.c This patch is an implementation following linux kernel patch: " commit 1c4b6c3bcf30d0804db0d0647d8ebeb862c6f7e5 Author: Gao Pan <b54642@freescale.com> Date: Fri Oct 23 20:28:54 2015 +0800 i2c: imx: implement bus recovery Implement bus recovery methods for i2c-imx so we can recover from situations where SCL/SDA are stuck low. Once i2c bus SCL/SDA are stuck low during transfer, config the i2c pinctrl to gpio mode by calling pinctrl sleep set function, and then use GPIO to emulate the i2c protocol to send nine dummy clock to recover i2c device. After recovery, set i2c pinctrl to default group setting. " See Documentation/devicetree/bindings/i2c/i2c-imx.txt for detailed description. 1. Introuduce scl_gpio/sda_gpio/bus in mxc_i2c_bus. 2. Discard the __weak attribute for i2c_idle_bus and implement it, since we have pinctrl driver/driver model gpio driver. We can use device tree, but not let board code to do this. 3. gpio state for mxc_i2c is not a must, but it is recommended. If there is no gpio state, driver will give tips, but not fail. 4. The i2c controller was first probed, default pinctrl state will be used, so when need to use gpio function, need to do "pinctrl_select_state(dev, "gpio")" and after force bus idle, need to switch back "pinctrl_select_state(dev, "default")". This is example about how to use the gpio force bus idle function: " &i2c1 { clock-frequency = <100000>; pinctrl-names = "default", "gpio"; pinctrl-0 = <&pinctrl_i2c1>; pinctrl-1 = <&pinctrl_i2c1_gpio>; scl-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>; sda-gpios = <&gpio1 29 GPIO_ACTIVE_HIGH>; status = "okay"; [....] }; [.....] pinctrl_i2c1_gpio: i2c1grp_gpio { fsl,pins = < MX6UL_PAD_UART4_TX_DATA__GPIO1_IO28 0x1b8b0 MX6UL_PAD_UART4_RX_DATA__GPIO1_IO29 0x1b8b0 >; }; " Signed-off-by: Peng Fan <van.freenix@gmail.com> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Stefano Babic <sbabic@denx.de> Cc: Heiko Schocher <hs@denx.de> Cc: Simon Glass <sjg@chromium.org> Cc: York Sun <york.sun@nxp.com>
2015-05-14i2c: mxc: refactor i2c driver and support dmPeng Fan
1. Introduce a new structure `struct mxc_i2c_bus`, this structure will used for non-DM and DM. 2. Remove `struct mxc_i2c_regs` structure, but use register offset to access registers based on `base` entry of `struct mxc_i2c_bus`. 3. Remove most `#ifdef I2C_QUIRK_REG`. Using driver_data to contain platform flags. A new flag is introduced, I2C_QUIRK_FLAG. 4. Most functions use `struct mxc_i2c_bus` as one of the parameters. Make most functions common to DM and non-DM, try to avoid duplicated code. 5. Support DM, but pinctrl is not included. Pinmux setting is still set by setup_i2c, but we do not need bus_i2c_init for DM. 6. struct i2c_parms and struct sram_data are removed. 7. Remove bus_i2c_read bus_i2c_write prototype in header file. The frist paramter of bus_i2c_init is modified to i2c index. Add new prototype i2c_idle_bus and force_bus_idle. Since bus_i2c_init is not good for DM I2C and pinctrl is missed, we use a weak function for i2c_idle_bus. Board file take the responsibility to implement this function, like this: " int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus) { if (i2c_bus->index == 0) force_bus_idle(i2c_pads_info0); else if (i2c_bus->index == 1) force_bus_idle(i2c_pads_info1); else xxxxxx } " 8. Introduce a weak function, enable_i2c_clk 9. Tested on an i.MX7 platform. Log info: => dm tree Class Probed Name ---------------------------------------- root [ + ] root_driver simple_bus [ ] |-- soc simple_bus [ ] | |-- aips-bus@30000000 simple_bus [ ] | | |-- anatop@30360000 simple_bus [ ] | | `-- snvs@30370000 simple_bus [ ] | |-- aips-bus@30400000 simple_bus [ ] | `-- aips-bus@30800000 i2c [ ] | |-- i2c@30a20000 i2c [ ] | `-- i2c@30a40000 simple_bus [ ] `-- regulators => i2c dev 0 Setting bus to 0 => i2c probe Valid chip addresses: 08 50 => i2c md 8 31 0031: 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08 Signed-off-by: Peng Fan <Peng.Fan@freescale.com> Acked-by: Simon Glass <sjg@chromium.org>
2014-10-22imx: Add error checking to setup_i2c()Simon Glass
Since this function can fail, check its return value. Signed-off-by: Simon Glass <sjg@chromium.org> Tested-by: Nikita Kiryanov <nikita@compulab.co.il>
2014-09-09i2c: imx: add macros to setup pads for multiple SoC typesNikita Kiryanov
Add macro which defines i2c_pads_info structs for multiple SoC types, and a macro which selects the appropriate struct based on CPU type, thus eliminating the need to manage multiple i2c pad configurations manually when supporting multiple SoC types. Cc: Stefano Babic <sbabic@denx.de> Cc: Tim Harvey <tharvey@gateworks.com> Acked-by: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
2013-07-24Add GPL-2.0+ SPDX-License-Identifier to source filesWolfgang Denk
Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
2012-07-31imx-common: add i2c.c for bus recovery supportTroy Kisky
Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>