[PATCH 0/3] Add QSPI support on r8a7791/koelsch

[PATCH 0/3] Add QSPI support on r8a7791/koelsch

[Geert Uytterhoeven]

This series adds support for the Spansion s25fl512s SPI FLASH on the
r8a7791-based Koelsch board:

    [1/3] pinctrl: sh-pfc: r8a7791: Add QSPI pin groups
    [2/3] ARM: shmobile: r8a7791: add QSPI clock
    [3/3] ARM: shmobile: Koelsch: Add QSPI support

This applies to non-multiplatform Koelsch only.  Multi-platform Koelsch
support will be added when the spi-rspi driver gains DT support.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

[PATCH 1/3] pinctrl: sh-pfc: r8a7791: Add QSPI pin groups

[Geert Uytterhoeven]

From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/pinctrl/sh-pfc/pfc-r8a7791.c |   27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/pinctrl/sh-pfc/pfc-r8a7791.c b/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
index 654bef369ab8..0070243c859e 100644
--- a/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
+++ b/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
@@ -2135,6 +2135,25 @@ static const unsigned int msiof2_tx_pins[] = {
 static const unsigned int msiof2_tx_mux[] = {
 	MSIOF2_TXD_MARK,
 };
+/* - QSPI ------------------------------------------------------------------- */
+static const unsigned int qspi_pins[] = {
+	/* SPCLK, MOSI_IO0, MISO_IO1, IO2, IO3, SSL */
+	RCAR_GP_PIN(1, 4), RCAR_GP_PIN(1, 5), RCAR_GP_PIN(1, 6),
+	RCAR_GP_PIN(1, 7), RCAR_GP_PIN(1, 8), RCAR_GP_PIN(1, 9),
+};
+static const unsigned int qspi_mux[] = {
+	SPCLK_MARK, MOSI_IO0_MARK, MISO_IO1_MARK,
+	IO2_MARK, IO3_MARK, SSL_MARK
+};
+static const unsigned int qspi_b_pins[] = {
+	/* SPCLK, MOSI_IO0, MISO_IO1, IO2, IO3, SSL */
+	RCAR_GP_PIN(6, 0), RCAR_GP_PIN(6, 1), RCAR_GP_PIN(6, 2),
+	RCAR_GP_PIN(6, 3), RCAR_GP_PIN(6, 4), RCAR_GP_PIN(6, 5),
+};
+static const unsigned int qspi_b_mux[] = {
+	SPCLK_B_MARK, MOSI_IO0_B_MARK, MISO_IO1_B_MARK,
+	IO2_B_MARK, IO3_B_MARK, SSL_B_MARK
+};
 /* - SCIF0 ------------------------------------------------------------------ */
 static const unsigned int scif0_data_pins[] = {
 	/* RX, TX */
@@ -2877,6 +2896,8 @@ static const struct sh_pfc_pin_group pinmux_groups[] = {
 	SH_PFC_PIN_GROUP(msiof2_ss2),
 	SH_PFC_PIN_GROUP(msiof2_rx),
 	SH_PFC_PIN_GROUP(msiof2_tx),
+	SH_PFC_PIN_GROUP(qspi),
+	SH_PFC_PIN_GROUP(qspi_b),
 	SH_PFC_PIN_GROUP(scif0_data),
 	SH_PFC_PIN_GROUP(scif0_data_b),
 	SH_PFC_PIN_GROUP(scif0_data_c),
@@ -3074,6 +3095,11 @@ static const char * const msiof2_groups[] = {
 	"msiof2_tx",
 };
 
+static const char * const qspi_groups[] = {
+	"qspi",
+	"qspi_b",
+};
+
 static const char * const scif0_groups[] = {
 	"scif0_data",
 	"scif0_data_b",
@@ -3230,6 +3256,7 @@ static const struct sh_pfc_function pinmux_functions[] = {
 	SH_PFC_FUNCTION(msiof0),
 	SH_PFC_FUNCTION(msiof1),
 	SH_PFC_FUNCTION(msiof2),
+	SH_PFC_FUNCTION(qspi),
 	SH_PFC_FUNCTION(scif0),
 	SH_PFC_FUNCTION(scif1),
 	SH_PFC_FUNCTION(scif2),
-- 
1.7.9.5

[PATCH 1/3] pinctrl: sh-pfc: r8a7791: Add QSPI pin groups

[Laurent Pinchart]

Hi Geert,

Thank you for the patch.

On Friday 03 January 2014 16:34:14 Geert Uytterhoeven wrote:
> From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/pinctrl/sh-pfc/pfc-r8a7791.c |   27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
> b/drivers/pinctrl/sh-pfc/pfc-r8a7791.c index 654bef369ab8..0070243c859e
> 100644
> --- a/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
> +++ b/drivers/pinctrl/sh-pfc/pfc-r8a7791.c
> @@ -2135,6 +2135,25 @@ static const unsigned int msiof2_tx_pins[] = {
>  static const unsigned int msiof2_tx_mux[] = {
>  	MSIOF2_TXD_MARK,
>  };
> +/* - QSPI
> ------------------------------------------------------------------- */
> +static const unsigned int qspi_pins[] = {
> +	/* SPCLK, MOSI_IO0, MISO_IO1, IO2, IO3, SSL */
> +	RCAR_GP_PIN(1, 4), RCAR_GP_PIN(1, 5), RCAR_GP_PIN(1, 6),
> +	RCAR_GP_PIN(1, 7), RCAR_GP_PIN(1, 8), RCAR_GP_PIN(1, 9),
> +};

The QSPI controller can be used in 1-bit, 2-bit or 4-mode mode, so you should 
split the pins group to allow that. You could use one pin group for the 
control signals (SPCLK and SSL), one group for 2-bit data (MOSI + MISO, or IO0 
+ IO1 depending on the mode) and one group for 4-bit data (IO0 + IO1 + IO2 + 
IO3).

I assume that usage of the SSL signal is always required. If that's not the 
case the control signals group should be split in two.

Similarly, if the hardware supports "write-only" mode (where the MISO signal 
isn't connected), that should be supported through a 1-bit data signals group.

> +static const unsigned int qspi_mux[] = {
> +	SPCLK_MARK, MOSI_IO0_MARK, MISO_IO1_MARK,
> +	IO2_MARK, IO3_MARK, SSL_MARK
> +};
> +static const unsigned int qspi_b_pins[] = {
> +	/* SPCLK, MOSI_IO0, MISO_IO1, IO2, IO3, SSL */
> +	RCAR_GP_PIN(6, 0), RCAR_GP_PIN(6, 1), RCAR_GP_PIN(6, 2),
> +	RCAR_GP_PIN(6, 3), RCAR_GP_PIN(6, 4), RCAR_GP_PIN(6, 5),
> +};
> +static const unsigned int qspi_b_mux[] = {
> +	SPCLK_B_MARK, MOSI_IO0_B_MARK, MISO_IO1_B_MARK,
> +	IO2_B_MARK, IO3_B_MARK, SSL_B_MARK
> +};
>  /* - SCIF0
> ------------------------------------------------------------------ */
> static const unsigned int scif0_data_pins[] = {
>  	/* RX, TX */
> @@ -2877,6 +2896,8 @@ static const struct sh_pfc_pin_group pinmux_groups[] =
> { SH_PFC_PIN_GROUP(msiof2_ss2),
>  	SH_PFC_PIN_GROUP(msiof2_rx),
>  	SH_PFC_PIN_GROUP(msiof2_tx),
> +	SH_PFC_PIN_GROUP(qspi),
> +	SH_PFC_PIN_GROUP(qspi_b),
>  	SH_PFC_PIN_GROUP(scif0_data),
>  	SH_PFC_PIN_GROUP(scif0_data_b),
>  	SH_PFC_PIN_GROUP(scif0_data_c),
> @@ -3074,6 +3095,11 @@ static const char * const msiof2_groups[] = {
>  	"msiof2_tx",
>  };
> 
> +static const char * const qspi_groups[] = {
> +	"qspi",
> +	"qspi_b",
> +};
> +
>  static const char * const scif0_groups[] = {
>  	"scif0_data",
>  	"scif0_data_b",
> @@ -3230,6 +3256,7 @@ static const struct sh_pfc_function pinmux_functions[]
> = { SH_PFC_FUNCTION(msiof0),
>  	SH_PFC_FUNCTION(msiof1),
>  	SH_PFC_FUNCTION(msiof2),
> +	SH_PFC_FUNCTION(qspi),
>  	SH_PFC_FUNCTION(scif0),
>  	SH_PFC_FUNCTION(scif1),
>  	SH_PFC_FUNCTION(scif2),
-- 
Regards,

Laurent Pinchart

[PATCH 1/3] pinctrl: sh-pfc: r8a7791: Add QSPI pin groups

[Geert Uytterhoeven]

On Tue, Jan 7, 2014 at 3:58 PM, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>> +static const unsigned int qspi_pins[] = {
>> +     /* SPCLK, MOSI_IO0, MISO_IO1, IO2, IO3, SSL */
>> +     RCAR_GP_PIN(1, 4), RCAR_GP_PIN(1, 5), RCAR_GP_PIN(1, 6),
>> +     RCAR_GP_PIN(1, 7), RCAR_GP_PIN(1, 8), RCAR_GP_PIN(1, 9),
>> +};
>
> The QSPI controller can be used in 1-bit, 2-bit or 4-mode mode, so you should
> split the pins group to allow that. You could use one pin group for the
> control signals (SPCLK and SSL), one group for 2-bit data (MOSI + MISO, or IO0
> + IO1 depending on the mode) and one group for 4-bit data (IO0 + IO1 + IO2 +
> IO3).

OK, while you can't mix "real" functions (half of the pins are FN2, the other
half FN3), I forgot you can still configure the SoC to use IO2 and IO3 for GPIO.

Will split in qspi_ctrl (2 control wires), qspi_data2 (2 data wires),
and qspi_data4 (4 data wires).

> I assume that usage of the SSL signal is always required. If that's not the
> case the control signals group should be split in two.
>
> Similarly, if the hardware supports "write-only" mode (where the MISO signal
> isn't connected), that should be supported through a 1-bit data signals group.

No, the hardware doesn't support three-wire mode.
Only four-wire (Single/Dual SPI) and six-wire (Quad SPI) are supported.

Thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH 2/3] ARM: shmobile: r8a7791: add QSPI clock

[Geert Uytterhoeven]

From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
---
 arch/arm/mach-shmobile/clock-r8a7791.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm/mach-shmobile/clock-r8a7791.c b/arch/arm/mach-shmobile/clock-r8a7791.c
index f5461262ee25..740c06968994 100644
--- a/arch/arm/mach-shmobile/clock-r8a7791.c
+++ b/arch/arm/mach-shmobile/clock-r8a7791.c
@@ -93,6 +93,7 @@ static struct clk main_clk = {
  */
 SH_FIXED_RATIO_CLK_SET(pll1_clk,		main_clk,	1, 1);
 SH_FIXED_RATIO_CLK_SET(pll3_clk,		main_clk,	1, 1);
+SH_FIXED_RATIO_CLK_SET(qspi_clk,		pll1_clk,	1, 1);
 
 /* fixed ratio clock */
 SH_FIXED_RATIO_CLK_SET(extal_div2_clk,		extal_clk,	1, 2);
@@ -114,6 +115,7 @@ static struct clk *main_clks[] = {
 	&pll3_clk,
 	&hp_clk,
 	&p_clk,
+	&qspi_clk,
 	&rclk_clk,
 	&mp_clk,
 	&cp_clk,
@@ -122,6 +124,7 @@ static struct clk *main_clks[] = {
 
 /* MSTP */
 enum {
+	MSTP917,
 	MSTP813,
 	MSTP726, MSTP724, MSTP723, MSTP721, MSTP720,
 	MSTP719, MSTP718, MSTP715, MSTP714,
@@ -133,6 +136,7 @@ enum {
 };
 
 static struct clk mstp_clks[MSTP_NR] = {
+	[MSTP917] = SH_CLK_MSTP32(&qspi_clk, SMSTPCR9, 17, 0), /* QSPI */
 	[MSTP813] = SH_CLK_MSTP32(&p_clk, SMSTPCR8, 13, 0), /* Ether */
 	[MSTP726] = SH_CLK_MSTP32(&zx_clk, SMSTPCR7, 26, 0), /* LVDS0 */
 	[MSTP724] = SH_CLK_MSTP32(&zx_clk, SMSTPCR7, 24, 0), /* DU0 */
@@ -167,6 +171,7 @@ static struct clk_lookup lookups[] = {
 	CLKDEV_CON_ID("pll3",		&pll3_clk),
 	CLKDEV_CON_ID("hp",		&hp_clk),
 	CLKDEV_CON_ID("p",		&p_clk),
+	CLKDEV_CON_ID("qspi",		&qspi_clk),
 	CLKDEV_CON_ID("rclk",		&rclk_clk),
 	CLKDEV_CON_ID("mp",		&mp_clk),
 	CLKDEV_CON_ID("cp",		&cp_clk),
@@ -192,6 +197,7 @@ static struct clk_lookup lookups[] = {
 	CLKDEV_DEV_ID("sh-sci.13", &mstp_clks[MSTP1106]), /* SCIFA4 */
 	CLKDEV_DEV_ID("sh-sci.14", &mstp_clks[MSTP1107]), /* SCIFA5 */
 	CLKDEV_DEV_ID("sh_cmt.0", &mstp_clks[MSTP124]),
+	CLKDEV_DEV_ID("qspi.0", &mstp_clks[MSTP917]),
 	CLKDEV_DEV_ID("e61f0000.thermal", &mstp_clks[MSTP522]),
 	CLKDEV_DEV_ID("rcar_thermal", &mstp_clks[MSTP522]),
 	CLKDEV_DEV_ID("r8a7791-ether", &mstp_clks[MSTP813]), /* Ether */
@@ -232,6 +238,11 @@ void __init r8a7791_clock_init(void)
 		break;
 	}
 
+	if ((mode & (MD(3) | MD(2) | MD(1))) == MD(2))
+		SH_CLK_SET_RATIO(&qspi_clk_ratio, 1, 16);
+	else
+		SH_CLK_SET_RATIO(&qspi_clk_ratio, 1, 20);
+
 	for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
 		ret = clk_register(main_clks[k]);
 
-- 
1.7.9.5

[PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support

[Geert Uytterhoeven]

From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>

Enable support for the Spansion s25fl512s SPI FLASH on the Koelsch board:
  - Add QSPI platform device, resources, platform data, and pinmux,
  - Add FLASH data and MTD partitions.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
---
 arch/arm/mach-shmobile/board-koelsch.c |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/arch/arm/mach-shmobile/board-koelsch.c b/arch/arm/mach-shmobile/board-koelsch.c
index de7cc64b1f37..723ed54b38be 100644
--- a/arch/arm/mach-shmobile/board-koelsch.c
+++ b/arch/arm/mach-shmobile/board-koelsch.c
@@ -25,12 +25,17 @@
 #include <linux/input.h>
 #include <linux/kernel.h>
 #include <linux/leds.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
 #include <linux/phy.h>
 #include <linux/pinctrl/machine.h>
 #include <linux/platform_data/gpio-rcar.h>
 #include <linux/platform_data/rcar-du.h>
 #include <linux/platform_device.h>
 #include <linux/sh_eth.h>
+#include <linux/spi/flash.h>
+#include <linux/spi/rspi.h>
+#include <linux/spi/spi.h>
 #include <mach/common.h>
 #include <mach/irqs.h>
 #include <mach/r8a7791.h>
@@ -148,6 +153,55 @@ static const struct gpio_keys_platform_data koelsch_keys_pdata __initconst = {
 	.nbuttons	= ARRAY_SIZE(gpio_buttons),
 };
 
+/* QSPI */
+static const struct resource qspi_resources[] __initconst = {
+	DEFINE_RES_MEM(0xe6b10000, 0x1000),
+	DEFINE_RES_IRQ(gic_spi(184)),
+};
+
+static const struct rspi_plat_data qspi_pdata __initconst = {
+	.num_chipselect = 1,
+};
+
+/* SPI Flash memory (Spansion S25FL512SAGMFIG11 64 MiB) */
+static struct mtd_partition spi_flash_part[] = {
+	{
+		.name		= "loader",
+		.offset		= 0x00000000,
+		.size		= 512 * 1024,
+		.mask_flags	= MTD_WRITEABLE,
+	},
+	{
+		.name		= "bootenv",
+		.offset		= MTDPART_OFS_APPEND,
+		.size		= 512 * 1024,
+		.mask_flags	= MTD_WRITEABLE,
+	},
+	{
+		.name		= "data",
+		.offset		= MTDPART_OFS_APPEND,
+		.size		= MTDPART_SIZ_FULL,
+	},
+};
+
+static const struct flash_platform_data spi_flash_data = {
+	.name		= "m25p80",
+	.parts		= spi_flash_part,
+	.nr_parts	= ARRAY_SIZE(spi_flash_part),
+	.type		= "s25fl512s",
+};
+
+static const struct spi_board_info spi_info[] __initconst = {
+	{
+		.modalias	= "m25p80",
+		.platform_data	= &spi_flash_data,
+		.mode		= SPI_MODE_0,
+		.max_speed_hz	= 30000000,
+		.bus_num	= 0,
+		.chip_select	= 0,
+	},
+};
+
 static const struct pinctrl_map koelsch_pinctrl_map[] = {
 	/* DU */
 	PIN_MAP_MUX_GROUP_DEFAULT("rcar-du-r8a7791", "pfc-r8a7791",
@@ -165,6 +219,8 @@ static const struct pinctrl_map koelsch_pinctrl_map[] = {
 				  "eth_rmii", "eth"),
 	PIN_MAP_MUX_GROUP_DEFAULT("r8a7791-ether", "pfc-r8a7791",
 				  "intc_irq0", "intc"),
+	/* QSPI */
+	PIN_MAP_MUX_GROUP_DEFAULT("qspi.0", "pfc-r8a7791", "qspi", "qspi"),
 	/* SCIF0 (CN19: DEBUG SERIAL0) */
 	PIN_MAP_MUX_GROUP_DEFAULT("sh-sci.6", "pfc-r8a7791",
 				  "scif0_data_d", "scif0"),
@@ -190,6 +246,11 @@ static void __init koelsch_add_standard_devices(void)
 	platform_device_register_data(&platform_bus, "gpio-keys", -1,
 				      &koelsch_keys_pdata,
 				      sizeof(koelsch_keys_pdata));
+	platform_device_register_resndata(&platform_bus, "qspi", 0,
+					  qspi_resources,
+					  ARRAY_SIZE(qspi_resources),
+					  &qspi_pdata, sizeof(qspi_pdata));
+	spi_register_board_info(spi_info, ARRAY_SIZE(spi_info));
 
 	koelsch_add_du_device();
 }
-- 
1.7.9.5

[PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support

[Sergei Shtylyov]

Hello.

On 01/03/2014 06:34 PM, Geert Uytterhoeven wrote:

> From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>

> Enable support for the Spansion s25fl512s SPI FLASH on the Koelsch board:
>    - Add QSPI platform device, resources, platform data, and pinmux,
>    - Add FLASH data and MTD partitions.

> Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
> ---
>   arch/arm/mach-shmobile/board-koelsch.c |   61 ++++++++++++++++++++++++++++++++
>   1 file changed, 61 insertions(+)

> diff --git a/arch/arm/mach-shmobile/board-koelsch.c b/arch/arm/mach-shmobile/board-koelsch.c
> index de7cc64b1f37..723ed54b38be 100644
> --- a/arch/arm/mach-shmobile/board-koelsch.c
> +++ b/arch/arm/mach-shmobile/board-koelsch.c
[...]
> @@ -190,6 +246,11 @@ static void __init koelsch_add_standard_devices(void)
>   	platform_device_register_data(&platform_bus, "gpio-keys", -1,
>   				      &koelsch_keys_pdata,
>   				      sizeof(koelsch_keys_pdata));
> +	platform_device_register_resndata(&platform_bus, "qspi", 0,

    As I understood, there's single QSPI controller, so why you pass 0, and 
not -1 here?

> +					  qspi_resources,
> +					  ARRAY_SIZE(qspi_resources),
> +					  &qspi_pdata, sizeof(qspi_pdata));
> +	spi_register_board_info(spi_info, ARRAY_SIZE(spi_info));

WBR, Sergei

[PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support

[Geert Uytterhoeven]

On Fri, Jan 3, 2014 at 5:51 PM, Sergei Shtylyov
<sergei.shtylyov@cogentembedded.com> wrote:
>> +       platform_device_register_resndata(&platform_bus, "qspi", 0,
>
>    As I understood, there's single QSPI controller, so why you pass 0, and
> not -1 here?

Indeed, there's only a single QSPI instance.
However, I choose to use "0" for consistency with Lager.
Mach-shmobile seems to use a mix of 0 and -1.

If the maintainer prefers -1, I can change that.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support

[Kuninori Morimoto]

Hi

> <sergei.shtylyov@cogentembedded.com> wrote:
> >> +       platform_device_register_resndata(&platform_bus, "qspi", 0,
> >
> >    As I understood, there's single QSPI controller, so why you pass 0, and
> > not -1 here?
> 
> Indeed, there's only a single QSPI instance.
> However, I choose to use "0" for consistency with Lager.
> Mach-shmobile seems to use a mix of 0 and -1.
> 
> If the maintainer prefers -1, I can change that.

In SPI driver case, spi master will use dynamic 
bus_num value if ID was -1 (in spi_register_master()).
Then, slave device can't be detected.
So, ID = 0 is reasonable even though single QSPI.

[PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support

[Simon Horman]

On Sun, Jan 05, 2014 at 04:39:14PM -0800, Kuninori Morimoto wrote:
> Hi
> 
> > <sergei.shtylyov@cogentembedded.com> wrote:
> > >> +       platform_device_register_resndata(&platform_bus, "qspi", 0,
> > >
> > >    As I understood, there's single QSPI controller, so why you pass 0, and
> > > not -1 here?
> > 
> > Indeed, there's only a single QSPI instance.
> > However, I choose to use "0" for consistency with Lager.
> > Mach-shmobile seems to use a mix of 0 and -1.
> > 
> > If the maintainer prefers -1, I can change that.
> 
> In SPI driver case, spi master will use dynamic 
> bus_num value if ID was -1 (in spi_register_master()).
> Then, slave device can't be detected.
> So, ID = 0 is reasonable even though single QSPI.

When it makes sense I prefer -1, however, in this case it
seems that 0 is a better choice.

[PATCH 0/3] Add QSPI support on r8a7791/koelsch

[Simon Horman]

On Fri, Jan 03, 2014 at 04:34:13PM +0100, Geert Uytterhoeven wrote:
> This series adds support for the Spansion s25fl512s SPI FLASH on the
> r8a7791-based Koelsch board:
> 
>     [1/3] pinctrl: sh-pfc: r8a7791: Add QSPI pin groups

I believe that Laurent should handle patch 1/3.

>     [2/3] ARM: shmobile: r8a7791: add QSPI clock
>     [3/3] ARM: shmobile: Koelsch: Add QSPI support

I believe that patch 3/3 depends on patch 1/3.
So I would like to wait for Laurent to handle patch 1/3.

Also, please post a patch to update the koelsch defconfig.

> This applies to non-multiplatform Koelsch only.  Multi-platform Koelsch
> support will be added when the spi-rspi driver gains DT support.