[PATCH v3 3/4] ARM: lpc32xx: Add pl08x virtual dma channels for spi and i2s

[Piotr Wojtaszczyk <piotr.wojtaszczyk@xxxxxxxxxxx>]

Some of the signals are multiplexed, multiplexer configured at a signal
request.

Signed-off-by: Piotr Wojtaszczyk <piotr.wojtaszczyk@xxxxxxxxxxx>
---
Changes for v3:
- Split previous commit for separate subsystems
- Add pl08x virtual dma channels for i2s1
- Add dma mux handling, required when requesting tx dma signal for i2s1

 arch/arm/mach-lpc32xx/phy3250.c | 111 +++++++++++++++++++++++++++++++-
 1 file changed, 110 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-lpc32xx/phy3250.c b/arch/arm/mach-lpc32xx/phy3250.c
index 5371bfaed799..2ec0411964f9 100644
--- a/arch/arm/mach-lpc32xx/phy3250.c
+++ b/arch/arm/mach-lpc32xx/phy3250.c
@@ -9,14 +9,18 @@
  */
 
 #include <linux/amba/pl08x.h>
+#include <linux/amba/pl022.h>
 #include <linux/mtd/lpc32xx_mlc.h>
 #include <linux/mtd/lpc32xx_slc.h>
 #include <linux/of_platform.h>
+#include <linux/spinlock.h>
 
 #include <asm/mach/arch.h>
 #include "common.h"
 #include "lpc32xx.h"
 
+static DEFINE_SPINLOCK(lpc32xx_pl08x_lock);
+
 static struct pl08x_channel_data pl08x_slave_channels[] = {
 	{
 		.bus_id = "nand-slc",
@@ -30,11 +34,97 @@ static struct pl08x_channel_data pl08x_slave_channels[] = {
 		.max_signal = 12,
 		.periph_buses = PL08X_AHB1,
 	},
+	{
+		.bus_id = "i2s0-tx",
+		.min_signal = 13,
+		.max_signal = 13,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "i2s0-rx",
+		.min_signal = 0,
+		.max_signal = 0,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "i2s1-tx",
+		.min_signal = 10,
+		.max_signal = 10,
+		.muxval = 1,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "i2s1-rx",
+		.min_signal = 2,
+		.max_signal = 2,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "ssp0-tx",
+		.min_signal = 15,
+		.max_signal = 15,
+		.muxval = 1,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "ssp0-rx",
+		.min_signal = 14,
+		.max_signal = 14,
+		.muxval = 1,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "ssp1-tx",
+		.min_signal = 11,
+		.max_signal = 11,
+		.muxval = 1,
+		.periph_buses = PL08X_AHB1,
+	},
+	{
+		.bus_id = "ssp1-rx",
+		.min_signal = 3,
+		.max_signal = 3,
+		.muxval = 1,
+		.periph_buses = PL08X_AHB1,
+	},
+};
+
+struct lpc32xx_pl08x_mux {
+	int signal;
+	void __iomem *addr;
+	int bit;
+};
+
+/* From LPC32x0 User manual "3.2.1 DMA request signals" */
+static const struct lpc32xx_pl08x_mux dma_mux[] = {
+	{3, LPC32XX_CLKPWR_SSP_CLK_CTRL, 5},
+	{10, LPC32XX_CLKPWR_I2S_CLK_CTRL, 4},
+	{11, LPC32XX_CLKPWR_SSP_CLK_CTRL, 4},
+	{14, LPC32XX_CLKPWR_SSP_CLK_CTRL, 3},
+	{15, LPC32XX_CLKPWR_SSP_CLK_CTRL, 2},
 };
 
 static int pl08x_get_signal(const struct pl08x_channel_data *cd)
 {
-	return cd->min_signal;
+	const int signal = cd->min_signal;
+	unsigned long flags;
+	int i, tmp;
+
+	/* Set corresponding dma mux bit if muxed */
+	for (i = 0; i < ARRAY_SIZE(dma_mux); i++) {
+		if (dma_mux[i].signal == signal) {
+			spin_lock_irqsave(&lpc32xx_pl08x_lock, flags);
+			tmp = __raw_readl(dma_mux[i].addr);
+			if (cd->muxval)
+				tmp |= BIT(dma_mux[i].bit);
+			else
+				tmp &= ~BIT(dma_mux[i].bit);
+			__raw_writel(tmp, dma_mux[i].addr);
+			spin_unlock_irqrestore(&lpc32xx_pl08x_lock, flags);
+			break;
+		}
+	}
+	return signal;
 }
 
 static void pl08x_put_signal(const struct pl08x_channel_data *cd, int ch)
@@ -61,12 +151,31 @@ static struct lpc32xx_mlc_platform_data lpc32xx_mlc_data = {
 	.dma_filter = pl08x_filter_id,
 };
 
+static struct pl022_ssp_controller lpc32xx_ssp_data[] = {
+	{
+		.bus_id = 0,
+		.enable_dma = 0,
+		.dma_filter = pl08x_filter_id,
+		.dma_tx_param = "ssp0-tx",
+		.dma_rx_param = "ssp0-rx",
+	},
+	{
+		.bus_id = 1,
+		.enable_dma = 0,
+		.dma_filter = pl08x_filter_id,
+		.dma_tx_param = "ssp1-tx",
+		.dma_rx_param = "ssp1-rx",
+	}
+};
+
 static const struct of_dev_auxdata lpc32xx_auxdata_lookup[] __initconst = {
 	OF_DEV_AUXDATA("arm,pl080", 0x31000000, "pl08xdmac", &pl08x_pd),
 	OF_DEV_AUXDATA("nxp,lpc3220-slc", 0x20020000, "20020000.flash",
 		       &lpc32xx_slc_data),
 	OF_DEV_AUXDATA("nxp,lpc3220-mlc", 0x200a8000, "200a8000.flash",
 		       &lpc32xx_mlc_data),
+	OF_DEV_AUXDATA("arm,pl022", 0x20084000, NULL, &lpc32xx_ssp_data[0]),
+	OF_DEV_AUXDATA("arm,pl022", 0x2008c000, NULL, &lpc32xx_ssp_data[1]),
 	{ }
 };
 
-- 
2.25.1