NVIDIA Tegra30 pinmux controller

The Tegra30 pinctrl binding is very similar to the Tegra20 pinctrl binding,
as described in nvidia,tegra20-pinmux.txt. In fact, this document assumes
that binding as a baseline, and only documents the differences between the
two bindings.

Required properties:
- compatible: "nvidia,tegra30-pinmux"
- reg: Should contain the register physical address and length for each of
  the pad control and mux registers.

Tegra30 adds the following optional properties for pin configuration subnodes:
- nvidia,enable-input: Integer. Enable the pin's input path. 0: no, 1: yes.
- nvidia,open-drain: Integer. Enable open drain mode. 0: no, 1: yes.
- nvidia,lock: Integer. Lock the pin configuration against further changes
    until reset. 0: no, 1: yes.
- nvidia,io-reset: Integer. Reset the IO path. 0: no, 1: yes.

As with Tegra20, see the Tegra TRM for complete details regarding which groups
support which functionality.

Valid values for pin and group names are:

  per-pin mux groups:

    These all support nvidia,function, nvidia,tristate, nvidia,pull,
    nvidia,enable-input, nvidia,lock. Some support nvidia,open-drain,
    nvidia,io-reset.

    clk_32k_out_pa0, uart3_cts_n_pa1, dap2_fs_pa2, dap2_sclk_pa3,
    dap2_din_pa4, dap2_dout_pa5, sdmmc3_clk_pa6, sdmmc3_cmd_pa7, gmi_a17_pb0,
    gmi_a18_pb1, lcd_pwr0_pb2, lcd_pclk_pb3, sdmmc3_dat3_pb4, sdmmc3_dat2_pb5,
    sdmmc3_dat1_pb6, sdmmc3_dat0_pb7, uart3_rts_n_pc0, lcd_pwr1_pc1,
    uart2_txd_pc2, uart2_rxd_pc3, gen1_i2c_scl_pc4, gen1_i2c_sda_pc5,
    lcd_pwr2_pc6, gmi_wp_n_pc7, sdmmc3_dat5_pd0, sdmmc3_dat4_pd1, lcd_dc1_pd2,
    sdmmc3_dat6_pd3, sdmmc3_dat7_pd4, vi_d1_pd5, vi_vsync_pd6, vi_hsync_pd7,
    lcd_d0_pe0, lcd_d1_pe1, lcd_d2_pe2, lcd_d3_pe3, lcd_d4_pe4, lcd_d5_pe5,
    lcd_d6_pe6, lcd_d7_pe7, lcd_d8_pf0, lcd_d9_pf1, lcd_d10_pf2, lcd_d11_pf3,
    lcd_d12_pf4, lcd_d13_pf5, lcd_d14_pf6, lcd_d15_pf7, gmi_ad0_pg0,
    gmi_ad1_pg1, gmi_ad2_pg2, gmi_ad3_pg3, gmi_ad4_pg4, gmi_ad5_pg5,
    gmi_ad6_pg6, gmi_ad7_pg7, gmi_ad8_ph0, gmi_ad9_ph1, gmi_ad10_ph2,
    gmi_ad11_ph3, gmi_ad12_ph4, gmi_ad13_ph5, gmi_ad14_ph6, gmi_ad15_ph7,
    gmi_wr_n_pi0, gmi_oe_n_pi1, gmi_dqs_pi2, gmi_cs6_n_pi3, gmi_rst_n_pi4,
    gmi_iordy_pi5, gmi_cs7_n_pi6, gmi_wait_pi7, gmi_cs0_n_pj0, lcd_de_pj1,
    gmi_cs1_n_pj2, lcd_hsync_pj3, lcd_vsync_pj4, uart2_cts_n_pj5,
    uart2_rts_n_pj6, gmi_a16_pj7, gmi_adv_n_pk0, gmi_clk_pk1, gmi_cs4_n_pk2,
    gmi_cs2_n_pk3, gmi_cs3_n_pk4, spdif_out_pk5, spdif_in_pk6, gmi_a19_pk7,
    vi_d2_pl0, vi_d3_pl1, vi_d4_pl2, vi_d5_pl3, vi_d6_pl4, vi_d7_pl5,
    vi_d8_pl6, vi_d9_pl7, lcd_d16_pm0, lcd_d17_pm1, lcd_d18_pm2, lcd_d19_pm3,
    lcd_d20_pm4, lcd_d21_pm5, lcd_d22_pm6, lcd_d23_pm7, dap1_fs_pn0,
    dap1_din_pn1, dap1_dout_pn2, dap1_sclk_pn3, lcd_cs0_n_pn4, lcd_sdout_pn5,
    lcd_dc0_pn6, hdmi_int_pn7, ulpi_data7_po0, ulpi_data0_po1, ulpi_data1_po2,
    ulpi_data2_po3, ulpi_data3_po4, ulpi_data4_po5, ulpi_data5_po6,
    ulpi_data6_po7, dap3_fs_pp0, dap3_din_pp1, dap3_dout_pp2, dap3_sclk_pp3,
    dap4_fs_pp4, dap4_din_pp5, dap4_dout_pp6, dap4_sclk_pp7, kb_col0_pq0,
    kb_col1_pq1, kb_col2_pq2, kb_col3_pq3, kb_col4_pq4, kb_col5_pq5,
    kb_col6_pq6, kb_col7_pq7, kb_row0_pr0, kb_row1_pr1, kb_row2_pr2,
    kb_row3_pr3, kb_row4_pr4, kb_row5_pr5, kb_row6_pr6, kb_row7_pr7,
    kb_row8_ps0, kb_row9_ps1, kb_row10_ps2, kb_row11_ps3, kb_row12_ps4,
    kb_row13_ps5, kb_row14_ps6, kb_row15_ps7, vi_pclk_pt0, vi_mclk_pt1,
    vi_d10_pt2, vi_d11_pt3, vi_d0_pt4, gen2_i2c_scl_pt5, gen2_i2c_sda_pt6,
    sdmmc4_cmd_pt7, pu0, pu1, pu2, pu3, pu4, pu5, pu6, jtag_rtck_pu7, pv0,
    pv1, pv2, pv3, ddc_scl_pv4, ddc_sda_pv5, crt_hsync_pv6, crt_vsync_pv7,
    lcd_cs1_n_pw0, lcd_m1_pw1, spi2_cs1_n_pw2, spi2_cs2_n_pw3, clk1_out_pw4,
    clk2_out_pw5, uart3_txd_pw6, uart3_rxd_pw7, spi2_mosi_px0, spi2_miso_px1,
    spi2_sck_px2, spi2_cs0_n_px3, spi1_mosi_px4, spi1_sck_px5, spi1_cs0_n_px6,
    spi1_miso_px7, ulpi_clk_py0, ulpi_dir_py1, ulpi_nxt_py2, ulpi_stp_py3,
    sdmmc1_dat3_py4, sdmmc1_dat2_py5, sdmmc1_dat1_py6, sdmmc1_dat0_py7,
    sdmmc1_clk_pz0, sdmmc1_cmd_pz1, lcd_sdin_pz2, lcd_wr_n_pz3, lcd_sck_pz4,
    sys_clk_req_pz5, pwr_i2c_scl_pz6, pwr_i2c_sda_pz7, sdmmc4_dat0_paa0,
    sdmmc4_dat1_paa1, sdmmc4_dat2_paa2, sdmmc4_dat3_paa3, sdmmc4_dat4_paa4,
    sdmmc4_dat5_paa5, sdmmc4_dat6_paa6, sdmmc4_dat7_paa7, pbb0,
    cam_i2c_scl_pbb1, cam_i2c_sda_pbb2, pbb3, pbb4, pbb5, pbb6, pbb7,
    cam_mclk_pcc0, pcc1, pcc2, sdmmc4_rst_n_pcc3, sdmmc4_clk_pcc4,
    clk2_req_pcc5, pex_l2_rst_n_pcc6, pex_l2_clkreq_n_pcc7,
    pex_l0_prsnt_n_pdd0, pex_l0_rst_n_pdd1, pex_l0_clkreq_n_pdd2,
    pex_wake_n_pdd3, pex_l1_prsnt_n_pdd4, pex_l1_rst_n_pdd5,
    pex_l1_clkreq_n_pdd6, pex_l2_prsnt_n_pdd7, clk3_out_pee0, clk3_req_pee1,
    clk1_req_pee2, hdmi_cec_pee3, clk_32k_in, core_pwr_req, cpu_pwr_req, owr,
    pwr_int_n.

  drive groups:

    These all support nvidia,pull-down-strength, nvidia,pull-up-strength,
    nvidia,slew-rate-rising, nvidia,slew-rate-falling. Most but not all
    support nvidia,high-speed-mode, nvidia,schmitt, nvidia,low-power-mode.

    ao1, ao2, at1, at2, at3, at4, at5, cdev1, cdev2, cec, crt, csus, dap1,
    dap2, dap3, dap4, dbg, ddc, dev3, gma, gmb, gmc, gmd, gme, gmf, gmg,
    gmh, gpv, lcd1, lcd2, owr, sdio1, sdio2, sdio3, spi, uaa, uab, uart2,
    uart3, uda, vi1.

Example:

	pinctrl@70000000 {
		compatible = "nvidia,tegra30-pinmux";
		reg = < 0x70000868 0xd0     /* Pad control registers */
			0x70003000 0x3e0 >; /* Mux registers */
	};

Example board file extract:

	pinctrl@70000000 {
		sdmmc4_default: pinmux {
			sdmmc4_clk_pcc4 {
				nvidia,pins =	"sdmmc4_clk_pcc4",
						"sdmmc4_rst_n_pcc3";
				nvidia,function = "sdmmc4";
				nvidia,pull = <0>;
				nvidia,tristate = <0>;
			};
			sdmmc4_dat0_paa0 {
				nvidia,pins =	"sdmmc4_dat0_paa0",
						"sdmmc4_dat1_paa1",
						"sdmmc4_dat2_paa2",
						"sdmmc4_dat3_paa3",
						"sdmmc4_dat4_paa4",
						"sdmmc4_dat5_paa5",
						"sdmmc4_dat6_paa6",
						"sdmmc4_dat7_paa7";
				nvidia,function = "sdmmc4";
				nvidia,pull = <2>;
				nvidia,tristate = <0>;
			};
		};
	};

	sdhci@78000400 {
		pinctrl-names = "default";
		pinctrl-0 = <&sdmmc4_default>;
	};