leds: Add SN3218 and SN3216 support to the IS31FL32XX driver

Si-En Technology was acquired by ISSI in 2011, and it appears that
the IS31FL3218/IS31FL3216 are just rebranded SN3218/SN3216 devices.

Add the "si-en,sn3218" and "si-en,sn3216" compatible strings into the
IS31FL32XX driver as aliases for the issi equivalents, and update
binding documentation.

Datasheets:
IS31FL3218: http://www.issi.com/WW/pdf/31FL3218.pdf
SN3218: http://www.si-en.com/uploadpdf/s2011517171720.pdf

IS31FL3216: http://www.issi.com/WW/pdf/31FL3216.pdf
SN3216: http://www.si-en.com/uploadpdf/SN3216201152410148.pdf

Signed-off-by: David Rivshin <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Tested-by: Stefan Wahren <[e-mail]>
Signed-off-by: Jacek Anaszewski <[e-mail]>

Documentation/devicetree/bindings/leds/leds-is31fl32xx.txt

···
-Binding for ISSI IS31FL32xx LED Drivers
+Binding for ISSI IS31FL32xx and Si-En SN32xx LED Drivers
 
-The IS31FL32xx family of LED drivers are I2C devices with multiple
+The IS31FL32xx/SN32xx family of LED drivers are I2C devices with multiple
 constant-current channels, each with independent 256-level PWM control.
 Each LED is represented as a sub-node of the device.
 
···
 	issi,is31fl3235
 	issi,is31fl3218
 	issi,is31fl3216
+	si-en,sn3218
+	si-en,sn3216
 - reg: I2C slave address
 - address-cells : must be 1
 - size-cells : must be 0
···
 	};
 };
 
-For more product information please see the link below:
+For more product information please see the links below:
 http://www.issi.com/US/product-analog-fxled-driver.shtml
+http://www.si-en.com/product.asp?parentid=890

drivers/leds/Kconfig

···
 	tristate "LED support for ISSI IS31FL32XX I2C LED controller family"
 	depends on LEDS_CLASS && I2C && OF
 	help
-	  Say Y here to include support for ISSI IS31FL32XX LED controllers.
-	  They are I2C devices with multiple constant-current channels, each
-	  with independent 256-level PWM control.
+	  Say Y here to include support for ISSI IS31FL32XX and Si-En SN32xx
+	  LED controllers. They are I2C devices with multiple constant-current
+	  channels, each with independent 256-level PWM control.
 
 comment "LED driver for blink(1) USB RGB LED is under Special HID drivers (HID_THINGM)"
 

drivers/leds/leds-is31fl32xx.c

···
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
- * Datasheets: http://www.issi.com/US/product-analog-fxled-driver.shtml
+ * Datasheets:
+ *   http://www.issi.com/US/product-analog-fxled-driver.shtml
+ *   http://www.si-en.com/product.asp?parentid=890
  */
 
 #include <linux/device.h>
···
 	{ .compatible = "issi,is31fl3236", .data = &is31fl3236_cdef, },
 	{ .compatible = "issi,is31fl3235", .data = &is31fl3235_cdef, },
 	{ .compatible = "issi,is31fl3218", .data = &is31fl3218_cdef, },
+	{ .compatible = "si-en,sn3218",    .data = &is31fl3218_cdef, },
 	{ .compatible = "issi,is31fl3216", .data = &is31fl3216_cdef, },
+	{ .compatible = "si-en,sn3216",    .data = &is31fl3216_cdef, },
 	{},
 };