avr32: function for independently setting up SPI slaves

at32ap_spi_setup_slaves() is exposed to allow the addition of SPI slaves
to a SPI bus that has already been registered.  This is especially
useful for add-on cards, which have their own board setup function.
at32ap_spi_add_device() has been slightly re-organized, but should be
transparent to existing users.

So to add a SPI slave, after a SPI bus has already been registered:

	/* Configure the list of slaves on SPI controller "id" */
	at32_spi_setup_slaves(id,spi_board_info,ARRAY_SIZE(spi_board_info));
 	/* Register the list of slaves */
 	spi_register_board_info(spi_board_info,ARRAY_SIZE(spi_board_info));

Signed-off-by: Peter Ma <pma@mediamatech.com>
[haavard.skinnemoen@atmel.com: trivial whitespace fix]
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

2 files changed, 20 insertions, 16 deletions

diff --git a/arch/avr32/mach-at32ap/at32ap700x.c b/arch/avr32/mach-at32ap/at32ap700x.c
index eb9d4dc2e86..a47592e2fc3 100644
--- a/arch/avr32/mach-at32ap/at32ap700x.c
+++ b/arch/avr32/mach-at32ap/at32ap700x.c
@@ -1181,19 +1181,32 @@ static struct resource atmel_spi1_resource[] = {
 DEFINE_DEV(atmel_spi, 1);
 DEV_CLK(spi_clk, atmel_spi1, pba, 1);
 
-static void __init
-at32_spi_setup_slaves(unsigned int bus_num, struct spi_board_info *b,
-                      unsigned int n, const u8 *pins)
+void __init
+at32_spi_setup_slaves(unsigned int bus_num, struct spi_board_info *b, unsigned int n)
 {
+        /*
+         * Manage the chipselects as GPIOs, normally using the same pins
+         * the SPI controller expects; but boards can use other pins.
+         */
+        static u8 __initdata spi_pins[][4] = {
+                { GPIO_PIN_PA(3), GPIO_PIN_PA(4),
+                  GPIO_PIN_PA(5), GPIO_PIN_PA(20) },
+                { GPIO_PIN_PB(2), GPIO_PIN_PB(3),
+                  GPIO_PIN_PB(4), GPIO_PIN_PA(27) },
+        };
         unsigned int pin, mode;
 
+        /* There are only 2 SPI controllers */
+        if (bus_num > 1)
+                return;
+
         for (; n; n--, b++) {
                 b->bus_num = bus_num;
                 if (b->chip_select >= 4)
                         continue;
                 pin = (unsigned)b->controller_data;
                 if (!pin) {
-                        pin = pins[b->chip_select];
+                        pin = spi_pins[bus_num][b->chip_select];
                         b->controller_data = (void *)pin;
                 }
                 mode = AT32_GPIOF_OUTPUT;
@@ -1206,16 +1219,6 @@ at32_spi_setup_slaves(unsigned int bus_num, struct spi_board_info *b,
 struct platform_device *__init
 at32_add_device_spi(unsigned int id, struct spi_board_info *b, unsigned int n)
 {
-        /*
-         * Manage the chipselects as GPIOs, normally using the same pins
-         * the SPI controller expects; but boards can use other pins.
-         */
-        static u8 __initdata spi0_pins[] =
-                { GPIO_PIN_PA(3), GPIO_PIN_PA(4),
-                  GPIO_PIN_PA(5), GPIO_PIN_PA(20), };
-        static u8 __initdata spi1_pins[] =
-                { GPIO_PIN_PB(2), GPIO_PIN_PB(3),
-                  GPIO_PIN_PB(4), GPIO_PIN_PA(27), };
         struct platform_device *pdev;
         u32 pin_mask;
 
@@ -1228,7 +1231,7 @@ at32_add_device_spi(unsigned int id, struct spi_board_info *b, unsigned int n)
                 select_peripheral(PIOA, (1 << 0), PERIPH_A, AT32_GPIOF_PULLUP);
                 select_peripheral(PIOA, pin_mask, PERIPH_A, 0);
 
-                at32_spi_setup_slaves(0, b, n, spi0_pins);
+                at32_spi_setup_slaves(0, b, n);
                 break;
 
         case 1:
@@ -1239,7 +1242,7 @@ at32_add_device_spi(unsigned int id, struct spi_board_info *b, unsigned int n)
                 select_peripheral(PIOB, (1 << 0), PERIPH_B, AT32_GPIOF_PULLUP);
                 select_peripheral(PIOB, pin_mask, PERIPH_B, 0);
 
-                at32_spi_setup_slaves(1, b, n, spi1_pins);
+                at32_spi_setup_slaves(1, b, n);
                 break;
 
         default:
diff --git a/arch/avr32/mach-at32ap/include/mach/board.h b/arch/avr32/mach-at32ap/include/mach/board.h
index ddedb471f33..c7f25bb1d06 100644
--- a/arch/avr32/mach-at32ap/include/mach/board.h
+++ b/arch/avr32/mach-at32ap/include/mach/board.h
@@ -49,6 +49,7 @@ at32_add_device_eth(unsigned int id, struct eth_platform_data *data);
 struct spi_board_info;
 struct platform_device *
 at32_add_device_spi(unsigned int id, struct spi_board_info *b, unsigned int n);
+void at32_spi_setup_slaves(unsigned int bus_num, struct spi_board_info *b, unsigned int n);
 
 struct atmel_lcdfb_info;
 struct platform_device *