blackfin: add bf6xx spi driver

Spi driver for bf60x is different from old one, so implement a new
driver for it.

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>

2 files changed, 309 insertions, 0 deletions

diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 83abcbd..b8264df 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -31,6 +31,7 @@ COBJS-$(CONFIG_ARMADA100_SPI) += armada100_spi.o
 COBJS-$(CONFIG_ATMEL_DATAFLASH_SPI) += atmel_dataflash_spi.o
 COBJS-$(CONFIG_ATMEL_SPI) += atmel_spi.o
 COBJS-$(CONFIG_BFIN_SPI) += bfin_spi.o
+COBJS-$(CONFIG_BFIN_SPI6XX) += bfin_spi6xx.o
 COBJS-$(CONFIG_CF_SPI) += cf_spi.o
 COBJS-$(CONFIG_CF_QSPI) += cf_qspi.o
 COBJS-$(CONFIG_DAVINCI_SPI) += davinci_spi.o
diff --git a/drivers/spi/bfin_spi6xx.c b/drivers/spi/bfin_spi6xx.c
new file mode 100644
index 0000000..fde3447
--- /dev/null
+++ b/drivers/spi/bfin_spi6xx.c
@@ -0,0 +1,308 @@
+/*
+ * Analog Devices SPI3 controller driver
+ *
+ * Copyright (c) 2011 Analog Devices Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+
+#include <asm/blackfin.h>
+#include <asm/gpio.h>
+#include <asm/portmux.h>
+#include <asm/mach-common/bits/spi6xx.h>
+
+struct bfin_spi_slave {
+	struct spi_slave slave;
+	u32 control, clock;
+	struct bfin_spi_regs *regs;
+	int cs_pol;
+};
+
+#define to_bfin_spi_slave(s) container_of(s, struct bfin_spi_slave, slave)
+
+#define gpio_cs(cs) ((cs) - MAX_CTRL_CS)
+#ifdef CONFIG_BFIN_SPI_GPIO_CS
+# define is_gpio_cs(cs) ((cs) > MAX_CTRL_CS)
+#else
+# define is_gpio_cs(cs) 0
+#endif
+
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+	if (is_gpio_cs(cs))
+		return gpio_is_valid(gpio_cs(cs));
+	else
+		return (cs >= 1 && cs <= MAX_CTRL_CS);
+}
+
+void spi_cs_activate(struct spi_slave *slave)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+
+	if (is_gpio_cs(slave->cs)) {
+		unsigned int cs = gpio_cs(slave->cs);
+		gpio_set_value(cs, bss->cs_pol);
+	} else {
+		u32 ssel;
+		ssel = bfin_read32(&bss->regs->ssel);
+		ssel |= 1 << slave->cs;
+		if (bss->cs_pol)
+			ssel |= (1 << 8) << slave->cs;
+		else
+			ssel &= ~((1 << 8) << slave->cs);
+		bfin_write32(&bss->regs->ssel, ssel);
+	}
+
+	SSYNC();
+}
+
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+
+	if (is_gpio_cs(slave->cs)) {
+		unsigned int cs = gpio_cs(slave->cs);
+		gpio_set_value(cs, !bss->cs_pol);
+	} else {
+		u32 ssel;
+		ssel = bfin_read32(&bss->regs->ssel);
+		if (bss->cs_pol)
+			ssel &= ~((1 << 8) << slave->cs);
+		else
+			ssel |= (1 << 8) << slave->cs;
+		/* deassert cs */
+		bfin_write32(&bss->regs->ssel, ssel);
+		SSYNC();
+		/* disable cs */
+		ssel &= ~(1 << slave->cs);
+		bfin_write32(&bss->regs->ssel, ssel);
+	}
+
+	SSYNC();
+}
+
+void spi_init()
+{
+}
+
+#define SPI_PINS(n) \
+	{ 0, P_SPI##n##_SCK, P_SPI##n##_MISO, P_SPI##n##_MOSI, 0 }
+static unsigned short pins[][5] = {
+#ifdef SPI0_REGBASE
+	[0] = SPI_PINS(0),
+#endif
+#ifdef SPI1_REGBASE
+	[1] = SPI_PINS(1),
+#endif
+#ifdef SPI2_REGBASE
+	[2] = SPI_PINS(2),
+#endif
+};
+
+#define SPI_CS_PINS(n) \
+	{ \
+		P_SPI##n##_SSEL1, P_SPI##n##_SSEL2, P_SPI##n##_SSEL3, \
+		P_SPI##n##_SSEL4, P_SPI##n##_SSEL5, P_SPI##n##_SSEL6, \
+		P_SPI##n##_SSEL7, \
+	}
+static const unsigned short cs_pins[][7] = {
+#ifdef SPI0_REGBASE
+	[0] = SPI_CS_PINS(0),
+#endif
+#ifdef SPI1_REGBASE
+	[1] = SPI_CS_PINS(1),
+#endif
+#ifdef SPI2_REGBASE
+	[2] = SPI_CS_PINS(2),
+#endif
+};
+
+void spi_set_speed(struct spi_slave *slave, uint hz)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+	ulong sclk;
+	u32 clock;
+
+	sclk = get_sclk1();
+	clock = sclk / hz;
+	if (clock)
+		clock--;
+	bss->clock = clock;
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+		unsigned int max_hz, unsigned int mode)
+{
+	struct bfin_spi_slave *bss;
+	u32 reg_base;
+
+	if (!spi_cs_is_valid(bus, cs))
+		return NULL;
+
+	if (bus >= ARRAY_SIZE(pins) || pins[bus] == NULL) {
+		debug("%s: invalid bus %u\n", __func__, bus);
+		return NULL;
+	}
+	switch (bus) {
+#ifdef SPI0_REGBASE
+	case 0:
+		reg_base = SPI0_REGBASE;
+		break;
+#endif
+#ifdef SPI1_REGBASE
+	case 1:
+		reg_base = SPI1_REGBASE;
+		break;
+#endif
+#ifdef SPI2_REGBASE
+	case 2:
+		reg_base = SPI2_REGBASE;
+		break;
+#endif
+	default:
+		return NULL;
+	}
+
+	bss = malloc(sizeof(*bss));
+	if (!bss)
+		return NULL;
+
+	bss->slave.bus = bus;
+	bss->slave.cs = cs;
+	bss->regs = (struct bfin_spi_regs *)reg_base;
+	bss->control = SPI_CTL_EN | SPI_CTL_MSTR;
+	if (mode & SPI_CPHA)
+		bss->control |= SPI_CTL_CPHA;
+	if (mode & SPI_CPOL)
+		bss->control |= SPI_CTL_CPOL;
+	if (mode & SPI_LSB_FIRST)
+		bss->control |= SPI_CTL_LSBF;
+	bss->control &= ~SPI_CTL_ASSEL;
+	bss->cs_pol = mode & SPI_CS_HIGH ? 1 : 0;
+	spi_set_speed(&bss->slave, max_hz);
+
+	return &bss->slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+	free(bss);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+
+	debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
+
+	if (is_gpio_cs(slave->cs)) {
+		unsigned int cs = gpio_cs(slave->cs);
+		gpio_request(cs, "bfin-spi");
+		gpio_direction_output(cs, !bss->cs_pol);
+		pins[slave->bus][0] = P_DONTCARE;
+	} else
+		pins[slave->bus][0] = cs_pins[slave->bus][slave->cs - 1];
+	peripheral_request_list(pins[slave->bus], "bfin-spi");
+
+	bfin_write32(&bss->regs->control, bss->control);
+	bfin_write32(&bss->regs->clock, bss->clock);
+	bfin_write32(&bss->regs->delay, 0x0);
+	bfin_write32(&bss->regs->rx_control, SPI_RXCTL_REN);
+	bfin_write32(&bss->regs->tx_control, SPI_TXCTL_TEN | SPI_TXCTL_TTI);
+	SSYNC();
+
+	return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+
+	debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
+
+	peripheral_free_list(pins[slave->bus]);
+	if (is_gpio_cs(slave->cs))
+		gpio_free(gpio_cs(slave->cs));
+
+	bfin_write32(&bss->regs->rx_control, 0x0);
+	bfin_write32(&bss->regs->tx_control, 0x0);
+	bfin_write32(&bss->regs->control, 0x0);
+	SSYNC();
+}
+
+#ifndef CONFIG_BFIN_SPI_IDLE_VAL
+# define CONFIG_BFIN_SPI_IDLE_VAL 0xff
+#endif
+
+static int spi_pio_xfer(struct bfin_spi_slave *bss, const u8 *tx, u8 *rx,
+			uint bytes)
+{
+	/* discard invalid rx data and empty rfifo */
+	while (!(bfin_read32(&bss->regs->status) & SPI_STAT_RFE))
+		bfin_read32(&bss->regs->rfifo);
+
+	while (bytes--) {
+		u8 value = (tx ? *tx++ : CONFIG_BFIN_SPI_IDLE_VAL);
+		debug("%s: tx:%x ", __func__, value);
+		bfin_write32(&bss->regs->tfifo, value);
+		SSYNC();
+		while (bfin_read32(&bss->regs->status) & SPI_STAT_RFE)
+			if (ctrlc())
+				return -1;
+		value = bfin_read32(&bss->regs->rfifo);
+		if (rx)
+			*rx++ = value;
+		debug("rx:%x\n", value);
+	}
+
+	return 0;
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
+		void *din, unsigned long flags)
+{
+	struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
+	const u8 *tx = dout;
+	u8 *rx = din;
+	uint bytes = bitlen / 8;
+	int ret = 0;
+
+	debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__,
+		slave->bus, slave->cs, bitlen, bytes, flags);
+
+	if (bitlen == 0)
+		goto done;
+
+	/* we can only do 8 bit transfers */
+	if (bitlen % 8) {
+		flags |= SPI_XFER_END;
+		goto done;
+	}
+
+	if (flags & SPI_XFER_BEGIN)
+		spi_cs_activate(slave);
+
+	ret = spi_pio_xfer(bss, tx, rx, bytes);
+
+ done:
+	if (flags & SPI_XFER_END)
+		spi_cs_deactivate(slave);
+
+	return ret;
+}