soc/tegra: pmc: Add I/O pad voltage support

I/O pins on Tegra SoCs are grouped into so-called I/O pads. Each such
pad can be used to control the common voltage signal level and power
state of the pins in the given pad.

I/O pads can be powered down even if the system is active, which can
save power from that I/O interface. For SoC generations prior to
Tegra124 the I/O pad voltage is automatically detected and hence the
system software doesn't need to configure it. However, starting with
Tegra210 the detection logic has been removed, so explicit control of
the I/O pad voltage by system software is required.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 95 insertions, 31 deletions

diff --git a/include/soc/tegra/pmc.h b/include/soc/tegra/pmc.h
index e9e5347..2f271d1 100644
--- a/include/soc/tegra/pmc.h
+++ b/include/soc/tegra/pmc.h
@@ -76,37 +76,73 @@ int tegra_pmc_cpu_remove_clamping(unsigned int cpuid);
 
 #define TEGRA_POWERGATE_3D0	TEGRA_POWERGATE_3D
 
-#define TEGRA_IO_RAIL_CSIA	0
-#define TEGRA_IO_RAIL_CSIB	1
-#define TEGRA_IO_RAIL_DSI	2
-#define TEGRA_IO_RAIL_MIPI_BIAS	3
-#define TEGRA_IO_RAIL_PEX_BIAS	4
-#define TEGRA_IO_RAIL_PEX_CLK1	5
-#define TEGRA_IO_RAIL_PEX_CLK2	6
-#define TEGRA_IO_RAIL_USB0	9
-#define TEGRA_IO_RAIL_USB1	10
-#define TEGRA_IO_RAIL_USB2	11
-#define TEGRA_IO_RAIL_USB_BIAS	12
-#define TEGRA_IO_RAIL_NAND	13
-#define TEGRA_IO_RAIL_UART	14
-#define TEGRA_IO_RAIL_BB	15
-#define TEGRA_IO_RAIL_AUDIO	17
-#define TEGRA_IO_RAIL_HSIC	19
-#define TEGRA_IO_RAIL_COMP	22
-#define TEGRA_IO_RAIL_HDMI	28
-#define TEGRA_IO_RAIL_PEX_CNTRL	32
-#define TEGRA_IO_RAIL_SDMMC1	33
-#define TEGRA_IO_RAIL_SDMMC3	34
-#define TEGRA_IO_RAIL_SDMMC4	35
-#define TEGRA_IO_RAIL_CAM	36
-#define TEGRA_IO_RAIL_RES	37
-#define TEGRA_IO_RAIL_HV	38
-#define TEGRA_IO_RAIL_DSIB	39
-#define TEGRA_IO_RAIL_DSIC	40
-#define TEGRA_IO_RAIL_DSID	41
-#define TEGRA_IO_RAIL_CSIE	44
-#define TEGRA_IO_RAIL_LVDS	57
-#define TEGRA_IO_RAIL_SYS_DDC	58
+/**
+ * enum tegra_io_pad - I/O pad group identifier
+ *
+ * I/O pins on Tegra SoCs are grouped into so-called I/O pads. Each such pad
+ * can be used to control the common voltage signal level and power state of
+ * the pins of the given pad.
+ */
+enum tegra_io_pad {
+	TEGRA_IO_PAD_AUDIO,
+	TEGRA_IO_PAD_AUDIO_HV,
+	TEGRA_IO_PAD_BB,
+	TEGRA_IO_PAD_CAM,
+	TEGRA_IO_PAD_COMP,
+	TEGRA_IO_PAD_CSIA,
+	TEGRA_IO_PAD_CSIB,
+	TEGRA_IO_PAD_CSIC,
+	TEGRA_IO_PAD_CSID,
+	TEGRA_IO_PAD_CSIE,
+	TEGRA_IO_PAD_CSIF,
+	TEGRA_IO_PAD_DBG,
+	TEGRA_IO_PAD_DEBUG_NONAO,
+	TEGRA_IO_PAD_DMIC,
+	TEGRA_IO_PAD_DP,
+	TEGRA_IO_PAD_DSI,
+	TEGRA_IO_PAD_DSIB,
+	TEGRA_IO_PAD_DSIC,
+	TEGRA_IO_PAD_DSID,
+	TEGRA_IO_PAD_EMMC,
+	TEGRA_IO_PAD_EMMC2,
+	TEGRA_IO_PAD_GPIO,
+	TEGRA_IO_PAD_HDMI,
+	TEGRA_IO_PAD_HSIC,
+	TEGRA_IO_PAD_HV,
+	TEGRA_IO_PAD_LVDS,
+	TEGRA_IO_PAD_MIPI_BIAS,
+	TEGRA_IO_PAD_NAND,
+	TEGRA_IO_PAD_PEX_BIAS,
+	TEGRA_IO_PAD_PEX_CLK1,
+	TEGRA_IO_PAD_PEX_CLK2,
+	TEGRA_IO_PAD_PEX_CNTRL,
+	TEGRA_IO_PAD_SDMMC1,
+	TEGRA_IO_PAD_SDMMC3,
+	TEGRA_IO_PAD_SDMMC4,
+	TEGRA_IO_PAD_SPI,
+	TEGRA_IO_PAD_SPI_HV,
+	TEGRA_IO_PAD_SYS_DDC,
+	TEGRA_IO_PAD_UART,
+	TEGRA_IO_PAD_USB0,
+	TEGRA_IO_PAD_USB1,
+	TEGRA_IO_PAD_USB2,
+	TEGRA_IO_PAD_USB3,
+	TEGRA_IO_PAD_USB_BIAS,
+};
+
+/* deprecated, use TEGRA_IO_PAD_{HDMI,LVDS} instead */
+#define TEGRA_IO_RAIL_HDMI	TEGRA_IO_PAD_HDMI
+#define TEGRA_IO_RAIL_LVDS	TEGRA_IO_PAD_LVDS
+
+/**
+ * enum tegra_io_pad_voltage - voltage level of the I/O pad's source rail
+ * @TEGRA_IO_PAD_1800000UV: 1.8 V
+ * @TEGRA_IO_PAD_3300000UV: 3.3 V
+ */
+enum tegra_io_pad_voltage {
+	TEGRA_IO_PAD_1800000UV,
+	TEGRA_IO_PAD_3300000UV,
+};
 
 #ifdef CONFIG_ARCH_TEGRA
 int tegra_powergate_is_powered(unsigned int id);
@@ -118,6 +154,13 @@ int tegra_powergate_remove_clamping(unsigned int id);
 int tegra_powergate_sequence_power_up(unsigned int id, struct clk *clk,
 				      struct reset_control *rst);
 
+int tegra_io_pad_power_enable(enum tegra_io_pad id);
+int tegra_io_pad_power_disable(enum tegra_io_pad id);
+int tegra_io_pad_set_voltage(enum tegra_io_pad id,
+			     enum tegra_io_pad_voltage voltage);
+int tegra_io_pad_get_voltage(enum tegra_io_pad id);
+
+/* deprecated, use tegra_io_pad_power_{enable,disable}() instead */
 int tegra_io_rail_power_on(unsigned int id);
 int tegra_io_rail_power_off(unsigned int id);
 #else
@@ -148,6 +191,27 @@ static inline int tegra_powergate_sequence_power_up(unsigned int id,
 	return -ENOSYS;
 }
 
+static inline int tegra_io_pad_power_enable(enum tegra_io_pad id)
+{
+	return -ENOSYS;
+}
+
+static inline int tegra_io_pad_power_disable(enum tegra_io_pad id)
+{
+	return -ENOSYS;
+}
+
+static inline int tegra_io_pad_set_voltage(enum tegra_io_pad id,
+					   enum tegra_io_pad_voltage voltage)
+{
+	return -ENOSYS;
+}
+
+static inline int tegra_io_pad_get_voltage(enum tegra_io_pad id)
+{
+	return -ENOSYS;
+}
+
 static inline int tegra_io_rail_power_on(unsigned int id)
 {
 	return -ENOSYS;