radio: silabs: Add support for Silabs FM chip

Silicon Labs FM radio device

-FM RX playback with RDS

	FM signal is demodulated then audio L/R samples are sent to external audio codec.

	FM Rx RDS data received sent to host processor on I2C.

Required Properties:

- compatible: "silabs,silabs-fm"

Example:

	silabs,silabs-fm {

		compatible = "silabs,silabs-fm";

	};

Silicon Labs Si4705 FM radio

Silabs Si4705 is a FM radio chip which sits on the i2c bus.

This node must live under i2c controller.

Required properties:

 - compatible		: should be "silabs,si4705"

 - reg			: i2c slave address of the device

 - interrupt-parent	: parent of interrupt

 - interrupts		: interrupt to indicate completion of on going tune, seek etc.

 - silabs,int-gpio	: interrupt gpio

 - silabs,reset-gpio	: reset gpio

 - silabs,status-gpio	: status gpio

 - pinctrl-names : This should be defined if a target uses pinctrl framework.

			See "pinctrl" in Documentation/devicetree/bindings/pinctrl/msm-pinctrl.txt.

			It should specify the names of the configs that pinctrl can install in driver.

			Following are the pinctrl configs that can be installed:

			"pmx_fm_active" : Active configuration of pins, this should specify active

					config defined in pin groups of interrupt and reset gpio.

			"pmx_fm_suspend" : Disabled configuration of pins, this should specify sleep

					config defined in pin groups of interrupt and reset gpio.

- pinctrl		: Active and suspend configuration of interrupt and reset pins.

- interrupt-names	: Name of interrupt, must be "silabs_fm_int"

Optional properties:

 - vdd-supply		: Digital power supply needed to power device

 - va-supply		: Analog power supply needed to power device

Example:

	i2c_5: i2c@f9967000 { /* BLSP2 QUP5 */

		compatible = "qcom,i2c-msm-v2";

		#address-cells = <1>;

		#size-cells = <0>;

		reg-names = "qup_phys_addr", "bam_phys_addr";

		reg = <0xf9967000 0x1000>,

		      <0xf9944000 0x19000>;

		interrupt-names = "qup_irq", "bam_irq";

		interrupts = <0 105 0>, <0 239 0>;

		qcom,clk-freq-out = <100000>;

		qcom,clk-freq-in  = <19200000>;

		clock-names = "iface_clk", "core_clk";

		clocks = <&clock_gcc clk_gcc_blsp2_ahb_clk>,

			 <&clock_gcc clk_gcc_blsp2_qup5_i2c_apps_clk>;

		pinctrl-names = "i2c_active", "i2c_sleep";

		pinctrl-0 = <&i2c_5_active>;

		pinctrl-1 = <&i2c_5_sleep>;

		silabs4705@11 { /* SiLabs FM chip, slave id 0x11*/

			status = "ok";

			compatible = "silabs,si4705";

			reg = <0x11>;

			vdd-supply = <&pm8994_s4>;

			pinctrl-names = "pmx_fm_active","pmx_fm_suspend";

			pinctrl-0 = <&fm_int_active &fm_rst_active>;

			pinctrl-1 = <&fm_int_suspend &fm_rst_suspend>;

			silabs,reset-gpio = <&msm_gpio 62 0>;

			silabs,int-gpio = <&msm_gpio 9 0>;

			silabs,status-gpio = <&msm_gpio 11 0>;

			interrupt-parent = <&msm_gpio>;

			interrupts = <9 2>;

			interrupt-names = "silabs_fm_int";

			};

		};

          To compile this driver as a module, choose M here: the

          module will be called radio-iris-transport.

config RADIO_SILABS

        tristate "SILABS FM"

        depends on I2C && VIDEO_V4L2

        ---help---

          Say Y here if you want to use the SiLabs' FM chip

          with I2C as transport.

endif # RADIO_ADAPTERS

obj-$(CONFIG_RADIO_WL128X) += wl128x/

obj-$(CONFIG_RADIO_IRIS) += radio-iris.o

obj-$(CONFIG_RADIO_IRIS_TRANSPORT) += radio-iris-transport.o

obj-$(CONFIG_RADIO_SILABS) += silabs/

shark2-objs := radio-shark2.o radio-tea5777.o

obj-$(CONFIG_RADIO_SILABS) += radio-silabs-transport.o

obj-$(CONFIG_RADIO_SILABS) += radio-silabs.o