iio: DAC extension for ltc2634-12/10/8

This patch add support for Analog Devices (Linear Technology)
LTC2634 Quad 12-/10-/8-Bit Rail-to-Rail DAC.
The SPI functionality based on them from LTC2632 therefor
add the definitions only and update the Kconfig.
Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/dac/ltc2632.txt

-Linear Technology LTC2632/2636 DAC
+Linear Technology LTC2632/2634/2636 DAC
 
 Required properties:
  - compatible: Has to contain one of the following:
@@ -8,6 +8,12 @@ Required properties:
 	lltc,ltc2632-h12
 	lltc,ltc2632-h10
 	lltc,ltc2632-h8
+	lltc,ltc2634-l12
+	lltc,ltc2634-l10
+	lltc,ltc2634-l8
+	lltc,ltc2634-h12
+	lltc,ltc2634-h10
+	lltc,ltc2634-h8
 	lltc,ltc2636-l12
 	lltc,ltc2636-l10
 	lltc,ltc2636-l8

drivers/iio/dac/Kconfig

@@ -279,12 +279,12 @@ config LTC1660
 	  module will be called ltc1660.
 
 config LTC2632
-	tristate "Linear Technology LTC2632-12/10/8 and LTC2636-12/10/8 DAC spi driver"
+	tristate "Linear Technology LTC2632-12/10/8 and similar DAC spi driver"
 	depends on SPI
 	help
 	  Say yes here to build support for Linear Technology
-	  LTC2632-12, LTC2632-10, LTC2632-8, LTC2636-12, LTC2636-10 and
-	  LTC2636-8 converters (DAC).
+	  LTC2632, LTC2634 and LTC2636 DAC resolution 12/10/8 bit
+	  low 0-2.5V and high 0-4.096V range converters.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ltc2632.

drivers/iio/dac/ltc2632.c

@@ -56,6 +56,12 @@ enum ltc2632_supported_device_ids {
 	ID_LTC2632H12,
 	ID_LTC2632H10,
 	ID_LTC2632H8,
+	ID_LTC2634L12,
+	ID_LTC2634L10,
+	ID_LTC2634L8,
+	ID_LTC2634H12,
+	ID_LTC2634H10,
+	ID_LTC2634H8,
 	ID_LTC2636L12,
 	ID_LTC2636L10,
 	ID_LTC2636L8,
@@ -236,6 +242,36 @@ static const struct ltc2632_chip_info ltc2632_chip_info_tbl[] = {
 		.num_channels	= 2,
 		.vref_mv	= 4096,
 	},
+	[ID_LTC2634L12] = {
+		.channels	= ltc2632x12_channels,
+		.num_channels	= 4,
+		.vref_mv	= 2500,
+	},
+	[ID_LTC2634L10] = {
+		.channels	= ltc2632x10_channels,
+		.num_channels	= 4,
+		.vref_mv	= 2500,
+	},
+	[ID_LTC2634L8] =  {
+		.channels	= ltc2632x8_channels,
+		.num_channels	= 4,
+		.vref_mv	= 2500,
+	},
+	[ID_LTC2634H12] = {
+		.channels	= ltc2632x12_channels,
+		.num_channels	= 4,
+		.vref_mv	= 4096,
+	},
+	[ID_LTC2634H10] = {
+		.channels	= ltc2632x10_channels,
+		.num_channels	= 4,
+		.vref_mv	= 4096,
+	},
+	[ID_LTC2634H8] =  {
+		.channels	= ltc2632x8_channels,
+		.num_channels	= 4,
+		.vref_mv	= 4096,
+	},
 	[ID_LTC2636L12] = {
 		.channels	= ltc2632x12_channels,
 		.num_channels	= 8,
@@ -357,6 +393,12 @@ static const struct spi_device_id ltc2632_id[] = {
 	{ "ltc2632-h12", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2632H12] },
 	{ "ltc2632-h10", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2632H10] },
 	{ "ltc2632-h8", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2632H8] },
+	{ "ltc2634-l12", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634L12] },
+	{ "ltc2634-l10", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634L10] },
+	{ "ltc2634-l8", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634L8] },
+	{ "ltc2634-h12", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634H12] },
+	{ "ltc2634-h10", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634H10] },
+	{ "ltc2634-h8", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2634H8] },
 	{ "ltc2636-l12", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2636L12] },
 	{ "ltc2636-l10", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2636L10] },
 	{ "ltc2636-l8", (kernel_ulong_t)&ltc2632_chip_info_tbl[ID_LTC2636L8] },
@@ -386,6 +428,24 @@ static const struct of_device_id ltc2632_of_match[] = {
 	}, {
 		.compatible = "lltc,ltc2632-h8",
 		.data = &ltc2632_chip_info_tbl[ID_LTC2632H8]
+	}, {
+		.compatible = "lltc,ltc2634-l12",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634L12]
+	}, {
+		.compatible = "lltc,ltc2634-l10",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634L10]
+	}, {
+		.compatible = "lltc,ltc2634-l8",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634L8]
+	}, {
+		.compatible = "lltc,ltc2634-h12",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634H12]
+	}, {
+		.compatible = "lltc,ltc2634-h10",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634H10]
+	}, {
+		.compatible = "lltc,ltc2634-h8",
+		.data = &ltc2632_chip_info_tbl[ID_LTC2634H8]
 	}, {
 		.compatible = "lltc,ltc2636-l12",
 		.data = &ltc2632_chip_info_tbl[ID_LTC2636L12]