Merge remote-tracking branches 'spi/topic/fsl-espi', 'spi/topic/imx',...

Merge remote-tracking branches 'spi/topic/fsl-espi', 'spi/topic/imx', 'spi/topic/jcore', 'spi/topic/loopback' and 'spi/topic/meson' into spi-next

Documentation/devicetree/bindings/spi/jcore,spi.txt

+J-Core SPI master
+
+Required properties:
+
+- compatible: Must be "jcore,spi2".
+
+- reg: Memory region for registers.
+
+- #address-cells: Must be 1.
+
+- #size-cells: Must be 0.
+
+Optional properties:
+
+- clocks: If a phandle named "ref_clk" is present, SPI clock speed
+  programming is relative to the frequency of the indicated clock.
+  Necessary only if the input clock rate is something other than a
+  fixed 50 MHz.
+
+- clock-names: Clock names, one for each phandle in clocks.
+
+See spi-bus.txt for additional properties not specific to this device.
+
+Example:
+
+spi@40 {
+	compatible = "jcore,spi2";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	reg = <0x40 0x8>;
+	spi-max-frequency = <25000000>;
+	clocks = <&bus_clk>;
+	clock-names = "ref_clk";
+}

Documentation/devicetree/bindings/spi/spi-meson.txt

@@ -7,7 +7,7 @@ NOR memories, without DMA support and a 64-byte unified transmit /
 receive buffer.
 
 Required properties:
- - compatible: should be "amlogic,meson6-spifc"
+ - compatible: should be "amlogic,meson6-spifc" or "amlogic,meson-gxbb-spifc"
  - reg: physical base address and length of the controller registers
  - clocks: phandle of the input clock for the baud rate generator
  - #address-cells: should be 1

drivers/spi/Kconfig

@@ -295,6 +295,13 @@ config SPI_IMX
 	  This enables using the Freescale i.MX SPI controllers in master
 	  mode.
 
+config SPI_JCORE
+	tristate "J-Core SPI Master"
+	depends on OF && (SUPERH || COMPILE_TEST)
+	help
+	  This enables support for the SPI master controller in the J-Core
+	  synthesizable, open source SoC.
+
 config SPI_LM70_LLP
 	tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)"
 	depends on PARPORT

drivers/spi/Makefile

@@ -47,6 +47,7 @@ obj-$(CONFIG_SPI_FSL_SPI)		+= spi-fsl-spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi-gpio.o
 obj-$(CONFIG_SPI_IMG_SPFI)		+= spi-img-spfi.o
 obj-$(CONFIG_SPI_IMX)			+= spi-imx.o
+obj-$(CONFIG_SPI_JCORE)			+= spi-jcore.o
 obj-$(CONFIG_SPI_LM70_LLP)		+= spi-lm70llp.o
 obj-$(CONFIG_SPI_LP8841_RTC)		+= spi-lp8841-rtc.o
 obj-$(CONFIG_SPI_MESON_SPIFC)		+= spi-meson-spifc.o

drivers/spi/spi-fsl-lib.h

@@ -23,13 +23,14 @@
 /* SPI/eSPI Controller driver's private data. */
 struct mpc8xxx_spi {
 	struct device *dev;
-	void *reg_base;
+	void __iomem *reg_base;
 
 	/* rx & tx bufs from the spi_transfer */
 	const void *tx;
 	void *rx;
 #if IS_ENABLED(CONFIG_SPI_FSL_ESPI)
 	int len;
+	u8 *local_buf;
 #endif
 
 	int subblock;

drivers/spi/spi-imx.c

@@ -186,17 +186,19 @@ static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 
 /* MX1, MX31, MX35, MX51 CSPI */
 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
-		unsigned int fspi)
+		unsigned int fspi, unsigned int *fres)
 {
 	int i, div = 4;
 
 	for (i = 0; i < 7; i++) {
 		if (fspi * div >= fin)
-			return i;
+			goto out;
 		div <<= 1;
 	}
 
-	return 7;
+out:
+	*fres = fin / div;
+	return i;
 }
 
 static int spi_imx_bytes_per_word(const int bpw)
@@ -453,6 +455,9 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 #define MX31_CSPISTATUS		0x14
 #define MX31_STATUS_RR		(1 << 3)
 
+#define MX31_CSPI_TESTREG	0x1C
+#define MX31_TEST_LBC		(1 << 14)
+
 /* These functions also work for the i.MX35, but be aware that
  * the i.MX35 has a slightly different register layout for bits
  * we do not use here.
@@ -482,9 +487,11 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
 {
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
+	unsigned int clk;
 
-	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
+	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
 		MX31_CSPICTRL_DR_SHIFT;
+	spi_imx->spi_bus_clk = clk;
 
 	if (is_imx35_cspi(spi_imx)) {
 		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
@@ -506,6 +513,13 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
 
 	writel(reg, spi_imx->base + MXC_CSPICTRL);
 
+	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
+	if (spi->mode & SPI_LOOP)
+		reg |= MX31_TEST_LBC;
+	else
+		reg &= ~MX31_TEST_LBC;
+	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
+
 	return 0;
 }
 
@@ -625,9 +639,12 @@ static int mx1_config(struct spi_device *spi, struct spi_imx_config *config)
 {
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
+	unsigned int clk;
 
-	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
+	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
 		MX1_CSPICTRL_DR_SHIFT;
+	spi_imx->spi_bus_clk = clk;
+
 	reg |= config->bpw - 1;
 
 	if (spi->mode & SPI_CPHA)
@@ -1179,7 +1196,7 @@ static int spi_imx_probe(struct platform_device *pdev)
 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
-	if (is_imx51_ecspi(spi_imx))
+	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
 
 	init_completion(&spi_imx->xfer_done);
@@ -1251,6 +1268,12 @@ static int spi_imx_probe(struct platform_device *pdev)
 		goto out_clk_put;
 	}
 
+	if (!master->cs_gpios) {
+		dev_err(&pdev->dev, "No CS GPIOs available\n");
+		ret = -EINVAL;
+		goto out_clk_put;
+	}
+
 	for (i = 0; i < master->num_chipselect; i++) {
 		if (!gpio_is_valid(master->cs_gpios[i]))
 			continue;

drivers/spi/spi-jcore.c

+/*
+ * J-Core SPI controller driver
+ *
+ * Copyright (C) 2012-2016 Smart Energy Instruments, Inc.
+ *
+ * Current version by Rich Felker
+ * Based loosely on initial version by Oleksandr G Zhadan
+ *
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+
+#define DRV_NAME	"jcore_spi"
+
+#define CTRL_REG	0x0
+#define DATA_REG	0x4
+
+#define JCORE_SPI_CTRL_XMIT		0x02
+#define JCORE_SPI_STAT_BUSY		0x02
+#define JCORE_SPI_CTRL_LOOP		0x08
+#define JCORE_SPI_CTRL_CS_BITS		0x15
+
+#define JCORE_SPI_WAIT_RDY_MAX_LOOP	2000000
+
+struct jcore_spi {
+	struct spi_master *master;
+	void __iomem *base;
+	unsigned int cs_reg;
+	unsigned int speed_reg;
+	unsigned int speed_hz;
+	unsigned int clock_freq;
+};
+
+static int jcore_spi_wait(void __iomem *ctrl_reg)
+{
+	unsigned timeout = JCORE_SPI_WAIT_RDY_MAX_LOOP;
+
+	do {
+		if (!(readl(ctrl_reg) & JCORE_SPI_STAT_BUSY))
+			return 0;
+		cpu_relax();
+	} while (--timeout);
+
+	return -EBUSY;
+}
+
+static void jcore_spi_program(struct jcore_spi *hw)
+{
+	void __iomem *ctrl_reg = hw->base + CTRL_REG;
+
+	if (jcore_spi_wait(ctrl_reg))
+		dev_err(hw->master->dev.parent,
+			"timeout waiting to program ctrl reg.\n");
+
+	writel(hw->cs_reg | hw->speed_reg, ctrl_reg);
+}
+
+static void jcore_spi_chipsel(struct spi_device *spi, bool value)
+{
+	struct jcore_spi *hw = spi_master_get_devdata(spi->master);
+	u32 csbit = 1U << (2 * spi->chip_select);
+
+	dev_dbg(hw->master->dev.parent, "chipselect %d\n", spi->chip_select);
+
+	if (value)
+		hw->cs_reg |= csbit;
+	else
+		hw->cs_reg &= ~csbit;
+
+	jcore_spi_program(hw);
+}
+
+static void jcore_spi_baudrate(struct jcore_spi *hw, int speed)
+{
+	if (speed == hw->speed_hz) return;
+	hw->speed_hz = speed;
+	if (speed >= hw->clock_freq / 2)
+		hw->speed_reg = 0;
+	else
+		hw->speed_reg = ((hw->clock_freq / 2 / speed) - 1) << 27;
+	jcore_spi_program(hw);
+	dev_dbg(hw->master->dev.parent, "speed=%d reg=0x%x\n",
+		speed, hw->speed_reg);
+}
+
+static int jcore_spi_txrx(struct spi_master *master, struct spi_device *spi,
+			  struct spi_transfer *t)
+{
+	struct jcore_spi *hw = spi_master_get_devdata(master);
+
+	void __iomem *ctrl_reg = hw->base + CTRL_REG;
+	void __iomem *data_reg = hw->base + DATA_REG;
+	u32 xmit;
+
+	/* data buffers */
+	const unsigned char *tx;
+	unsigned char *rx;
+	unsigned int len;
+	unsigned int count;
+
+	jcore_spi_baudrate(hw, t->speed_hz);
+
+	xmit = hw->cs_reg | hw->speed_reg | JCORE_SPI_CTRL_XMIT;
+	tx = t->tx_buf;
+	rx = t->rx_buf;
+	len = t->len;
+
+	for (count = 0; count < len; count++) {
+		if (jcore_spi_wait(ctrl_reg))
+			break;
+
+		writel(tx ? *tx++ : 0, data_reg);
+		writel(xmit, ctrl_reg);
+
+		if (jcore_spi_wait(ctrl_reg))
+			break;
+
+		if (rx)
+			*rx++ = readl(data_reg);
+	}
+
+	spi_finalize_current_transfer(master);
+
+	if (count < len)
+		return -EREMOTEIO;
+
+	return 0;
+}
+
+static int jcore_spi_probe(struct platform_device *pdev)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct jcore_spi *hw;
+	struct spi_master *master;
+	struct resource *res;
+	u32 clock_freq;
+	struct clk *clk;
+	int err = -ENODEV;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(struct jcore_spi));
+	if (!master)
+		return err;
+
+	/* Setup the master state. */
+	master->num_chipselect = 3;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+	master->transfer_one = jcore_spi_txrx;
+	master->set_cs = jcore_spi_chipsel;
+	master->dev.of_node = node;
+	master->bus_num = pdev->id;
+
+	hw = spi_master_get_devdata(master);
+	hw->master = master;
+	platform_set_drvdata(pdev, hw);
+
+	/* Find and map our resources */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		goto exit_busy;
+	if (!devm_request_mem_region(&pdev->dev, res->start,
+				     resource_size(res), pdev->name))
+		goto exit_busy;
+	hw->base = devm_ioremap_nocache(&pdev->dev, res->start,
+					resource_size(res));
+	if (!hw->base)
+		goto exit_busy;
+
+	/*
+	 * The SPI clock rate controlled via a configurable clock divider
+	 * which is applied to the reference clock. A 50 MHz reference is
+	 * most suitable for obtaining standard SPI clock rates, but some
+	 * designs may have a different reference clock, and the DT must
+	 * make the driver aware so that it can properly program the
+	 * requested rate. If the clock is omitted, 50 MHz is assumed.
+	 */
+	clock_freq = 50000000;
+	clk = devm_clk_get(&pdev->dev, "ref_clk");
+	if (!IS_ERR_OR_NULL(clk)) {
+		if (clk_enable(clk) == 0)
+			clock_freq = clk_get_rate(clk);
+		else
+			dev_warn(&pdev->dev, "could not enable ref_clk\n");
+	}
+	hw->clock_freq = clock_freq;
+
+	/* Initialize all CS bits to high. */
+	hw->cs_reg = JCORE_SPI_CTRL_CS_BITS;
+	jcore_spi_baudrate(hw, 400000);
+
+	/* Register our spi controller */
+	err = devm_spi_register_master(&pdev->dev, master);
+	if (err)
+		goto exit;
+
+	return 0;
+
+exit_busy:
+	err = -EBUSY;
+exit:
+	spi_master_put(master);
+	return err;
+}
+
+static const struct of_device_id jcore_spi_of_match[] = {
+	{ .compatible = "jcore,spi2" },
+	{},
+};
+
+static struct platform_driver jcore_spi_driver = {
+	.probe = jcore_spi_probe,
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = jcore_spi_of_match,
+	},
+};
+
+module_platform_driver(jcore_spi_driver);
+
+MODULE_DESCRIPTION("J-Core SPI driver");
+MODULE_AUTHOR("Rich Felker <dalias@libc.org>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);

drivers/spi/spi-loopback-test.c

@@ -405,7 +405,7 @@ struct rx_ranges {
 	u8 *end;
 };
 
-int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
 {
 	struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list);
 	struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list);

drivers/spi/spi-meson-spifc.c

@@ -442,6 +442,7 @@ static const struct dev_pm_ops meson_spifc_pm_ops = {
 
 static const struct of_device_id meson_spifc_dt_match[] = {
 	{ .compatible = "amlogic,meson6-spifc", },
+	{ .compatible = "amlogic,meson-gxbb-spifc", },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, meson_spifc_dt_match);

include/linux/spi/spi.h

@@ -312,6 +312,8 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
  * @flags: other constraints relevant to this driver
  * @max_transfer_size: function that returns the max transfer size for
  *	a &spi_device; may be %NULL, so the default %SIZE_MAX will be used.
+ * @max_message_size: function that returns the max message size for
+ *	a &spi_device; may be %NULL, so the default %SIZE_MAX will be used.
  * @io_mutex: mutex for physical bus access
  * @bus_lock_spinlock: spinlock for SPI bus locking
  * @bus_lock_mutex: mutex for exclusion of multiple callers
@@ -442,10 +444,11 @@ struct spi_master {
 #define SPI_MASTER_MUST_TX      BIT(4)		/* requires tx */
 
 	/*
-	 * on some hardware transfer size may be constrained
+	 * on some hardware transfer / message size may be constrained
 	 * the limit may depend on device transfer settings
 	 */
 	size_t (*max_transfer_size)(struct spi_device *spi);
+	size_t (*max_message_size)(struct spi_device *spi);
 
 	/* I/O mutex */
 	struct mutex		io_mutex;
@@ -905,12 +908,26 @@ extern int spi_async_locked(struct spi_device *spi,
 			    struct spi_message *message);
 
 static inline size_t
-spi_max_transfer_size(struct spi_device *spi)
+spi_max_message_size(struct spi_device *spi)
 {
 	struct spi_master *master = spi->master;
-	if (!master->max_transfer_size)
+	if (!master->max_message_size)
 		return SIZE_MAX;
-	return master->max_transfer_size(spi);
+	return master->max_message_size(spi);
+}
+
+static inline size_t
+spi_max_transfer_size(struct spi_device *spi)
+{
+	struct spi_master *master = spi->master;
+	size_t tr_max = SIZE_MAX;
+	size_t msg_max = spi_max_message_size(spi);
+
+	if (master->max_transfer_size)
+		tr_max = master->max_transfer_size(spi);
+
+	/* transfer size limit must not be greater than messsage size limit */
+	return min(tr_max, msg_max);
 }
 
 /*---------------------------------------------------------------------------*/