spi: pxa2xx: Drop linux/spi/pxa2xx_spi.h

Merge series from Andy Shevchenko <andriy.shevchenko@linux.intel.com>:

As Arnd suggested we may drop linux/spi/pxa2xx_spi.h as most of
its content is being used solely internally to SPI subsystem
(PXA2xx drivers). Hence this refactoring series with the additional
win of getting rid of legacy documentation.

Note, that we have the only user of a single plain integer field
in the entire kernel for that. Switching to software nodes does not
diminish any of type checking as we only pass an integer.

5 files changed, 69 insertions, 118 deletions

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 993526308c4b..a2c99ff33e0a 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -832,8 +832,7 @@ config SPI_PXA2XX
 	select PXA_SSP if ARCH_PXA || ARCH_MMP
 	help
 	  This enables using a PXA2xx or Sodaville SSP port as a SPI master
-	  controller. The driver can be configured to use any SSP port and
-	  additional documentation can be found a Documentation/spi/pxa2xx.rst.
+	  controller. The driver can be configured to use any SSP port.
 
 config SPI_PXA2XX_PCI
 	def_tristate SPI_PXA2XX && PCI && COMMON_CLK
diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
index be563f0dd03a..08cb6e96ac94 100644
--- a/drivers/spi/spi-pxa2xx-dma.c
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -6,17 +6,22 @@
  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
  */
 
-#include <linux/device.h>
+#include <linux/atomic.h>
+#include <linux/dev_printk.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmaengine.h>
+#include <linux/errno.h>
+#include <linux/irqreturn.h>
 #include <linux/scatterlist.h>
-#include <linux/sizes.h>
+#include <linux/string.h>
+#include <linux/types.h>
 
-#include <linux/spi/pxa2xx_spi.h>
 #include <linux/spi/spi.h>
 
 #include "spi-pxa2xx.h"
 
+struct device;
+
 static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data,
 					     bool error)
 {
@@ -63,8 +68,6 @@ pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data,
 			   enum dma_transfer_direction dir,
 			   struct spi_transfer *xfer)
 {
-	struct chip_data *chip =
-		spi_get_ctldata(drv_data->controller->cur_msg->spi);
 	enum dma_slave_buswidth width;
 	struct dma_slave_config cfg;
 	struct dma_chan *chan;
@@ -89,14 +92,14 @@ pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data,
 	if (dir == DMA_MEM_TO_DEV) {
 		cfg.dst_addr = drv_data->ssp->phys_base + SSDR;
 		cfg.dst_addr_width = width;
-		cfg.dst_maxburst = chip->dma_burst_size;
+		cfg.dst_maxburst = drv_data->controller_info->dma_burst_size;
 
 		sgt = &xfer->tx_sg;
 		chan = drv_data->controller->dma_tx;
 	} else {
 		cfg.src_addr = drv_data->ssp->phys_base + SSDR;
 		cfg.src_addr_width = width;
-		cfg.src_maxburst = chip->dma_burst_size;
+		cfg.src_maxburst = drv_data->controller_info->dma_burst_size;
 
 		sgt = &xfer->rx_sg;
 		chan = drv_data->controller->dma_rx;
@@ -220,24 +223,3 @@ void pxa2xx_spi_dma_release(struct driver_data *drv_data)
 		controller->dma_tx = NULL;
 	}
 }
-
-int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
-					   struct spi_device *spi,
-					   u8 bits_per_word, u32 *burst_code,
-					   u32 *threshold)
-{
-	struct pxa2xx_spi_chip *chip_info = spi->controller_data;
-	struct driver_data *drv_data = spi_controller_get_devdata(spi->controller);
-	u32 dma_burst_size = drv_data->controller_info->dma_burst_size;
-
-	/*
-	 * If the DMA burst size is given in chip_info we use that,
-	 * otherwise we use the default. Also we use the default FIFO
-	 * thresholds for now.
-	 */
-	*burst_code = chip_info ? chip_info->dma_burst_size : dma_burst_size;
-	*threshold = SSCR1_RxTresh(RX_THRESH_DFLT)
-		   | SSCR1_TxTresh(TX_THRESH_DFLT);
-
-	return 0;
-}
diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index 861b21c63504..6d2efdb0e95f 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -6,15 +6,21 @@
  * Copyright (C) 2016, 2021 Intel Corporation
  */
 #include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/err.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
-
-#include <linux/spi/pxa2xx_spi.h>
+#include <linux/property.h>
+#include <linux/sprintf.h>
+#include <linux/string.h>
+#include <linux/types.h>
 
 #include <linux/dmaengine.h>
 #include <linux/platform_data/dma-dw.h>
 
+#include "spi-pxa2xx.h"
+
 #define PCI_DEVICE_ID_INTEL_QUARK_X1000		0x0935
 #define PCI_DEVICE_ID_INTEL_BYT			0x0f0e
 #define PCI_DEVICE_ID_INTEL_MRFLD		0x1194
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 2f60b2fde8d5..efe76d0c21bb 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -5,26 +5,29 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/atomic.h>
 #include <linux/bitops.h>
+#include <linux/bug.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/dmaengine.h>
 #include <linux/err.h>
-#include <linux/errno.h>
 #include <linux/gpio/consumer.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/io.h>
 #include <linux/ioport.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
+#include <linux/math64.h>
+#include <linux/minmax.h>
 #include <linux/mod_devicetable.h>
+#include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/property.h>
 #include <linux/slab.h>
+#include <linux/types.h>
 
-#include <linux/spi/pxa2xx_spi.h>
 #include <linux/spi/spi.h>
 
 #include "spi-pxa2xx.h"
@@ -63,6 +66,14 @@ MODULE_ALIAS("platform:pxa2xx-spi");
 				| CE4100_SSCR1_RFT | CE4100_SSCR1_TFT | SSCR1_MWDS \
 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
 
+struct chip_data {
+	u32 cr1;
+	u32 dds_rate;
+	u32 threshold;
+	u16 lpss_rx_threshold;
+	u16 lpss_tx_threshold;
+};
+
 #define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE	BIT(24)
 #define LPSS_CS_CONTROL_SW_MODE			BIT(0)
 #define LPSS_CS_CONTROL_CS_HIGH			BIT(1)
@@ -931,11 +942,11 @@ static bool pxa2xx_spi_can_dma(struct spi_controller *controller,
 			       struct spi_device *spi,
 			       struct spi_transfer *xfer)
 {
-	struct chip_data *chip = spi_get_ctldata(spi);
+	struct driver_data *drv_data = spi_controller_get_devdata(controller);
 
-	return chip->enable_dma &&
+	return drv_data->controller_info->enable_dma &&
 	       xfer->len <= MAX_DMA_LEN &&
-	       xfer->len >= chip->dma_burst_size;
+	       xfer->len >= drv_data->controller_info->dma_burst_size;
 }
 
 static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
@@ -944,9 +955,8 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
 {
 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
 	struct chip_data *chip = spi_get_ctldata(spi);
-	u32 dma_thresh = chip->dma_threshold;
-	u32 dma_burst = chip->dma_burst_size;
 	u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
+	u32 dma_thresh;
 	u32 clk_div;
 	u8 bits;
 	u32 speed;
@@ -956,7 +966,7 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
 	int dma_mapped;
 
 	/* Check if we can DMA this transfer */
-	if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
+	if (transfer->len > MAX_DMA_LEN && drv_data->controller_info->enable_dma) {
 		/* Warn ... we force this to PIO mode */
 		dev_warn_ratelimited(&spi->dev,
 				     "DMA disabled for transfer length %u greater than %d\n",
@@ -992,19 +1002,8 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
 		drv_data->read = drv_data->rx ? u32_reader : null_reader;
 		drv_data->write = drv_data->tx ? u32_writer : null_writer;
 	}
-	/*
-	 * If bits per word is changed in DMA mode, then must check
-	 * the thresholds and burst also.
-	 */
-	if (chip->enable_dma) {
-		if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
-						spi,
-						bits, &dma_burst,
-						&dma_thresh))
-			dev_warn_ratelimited(&spi->dev,
-					     "DMA burst size reduced to match bits_per_word\n");
-	}
 
+	dma_thresh = SSCR1_RxTresh(RX_THRESH_DFLT) | SSCR1_TxTresh(TX_THRESH_DFLT);
 	dma_mapped = controller->can_dma &&
 		     controller->can_dma(controller, spi, transfer) &&
 		     controller->cur_msg_mapped;
@@ -1067,7 +1066,7 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
 		pxa_ssp_disable(drv_data->ssp);
 
 	if (!pxa25x_ssp_comp(drv_data))
-		pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
+		pxa2xx_spi_write(drv_data, SSTO, TIMOUT_DFLT);
 
 	/* First set CR1 without interrupt and service enables */
 	pxa2xx_spi_update(drv_data, SSCR1, change_mask, cr1);
@@ -1151,7 +1150,6 @@ static int pxa2xx_spi_unprepare_transfer(struct spi_controller *controller)
 
 static int setup(struct spi_device *spi)
 {
-	struct pxa2xx_spi_chip *chip_info;
 	struct chip_data *chip;
 	const struct lpss_config *config;
 	struct driver_data *drv_data =
@@ -1210,28 +1208,6 @@ static int setup(struct spi_device *spi)
 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
 		if (!chip)
 			return -ENOMEM;
-
-		chip->enable_dma = drv_data->controller_info->enable_dma;
-		chip->timeout = TIMOUT_DFLT;
-	}
-
-	/*
-	 * Protocol drivers may change the chip settings, so...
-	 * if chip_info exists, use it.
-	 */
-	chip_info = spi->controller_data;
-
-	/* chip_info isn't always needed */
-	if (chip_info) {
-		if (chip_info->timeout)
-			chip->timeout = chip_info->timeout;
-		if (chip_info->tx_threshold)
-			tx_thres = chip_info->tx_threshold;
-		if (chip_info->tx_hi_threshold)
-			tx_hi_thres = chip_info->tx_hi_threshold;
-		if (chip_info->rx_threshold)
-			rx_thres = chip_info->rx_threshold;
-		chip->dma_threshold = 0;
 	}
 
 	chip->cr1 = 0;
@@ -1253,25 +1229,6 @@ static int setup(struct spi_device *spi)
 		chip->lpss_tx_threshold = tx_thres;
 	}
 
-	/*
-	 * Set DMA burst and threshold outside of chip_info path so that if
-	 * chip_info goes away after setting chip->enable_dma, the burst and
-	 * threshold can still respond to changes in bits_per_word.
-	 */
-	if (chip->enable_dma) {
-		/* Set up legal burst and threshold for DMA */
-		if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
-						spi->bits_per_word,
-						&chip->dma_burst_size,
-						&chip->dma_threshold)) {
-			dev_warn(&spi->dev,
-				 "in setup: DMA burst size reduced to match bits_per_word\n");
-		}
-		dev_dbg(&spi->dev,
-			"in setup: DMA burst size set to %u\n",
-			chip->dma_burst_size);
-	}
-
 	switch (drv_data->ssp_type) {
 	case QUARK_X1000_SSP:
 		chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
@@ -1357,6 +1314,7 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
 	struct ssp_device *ssp = NULL;
 	const void *match;
 	bool is_lpss_priv;
+	u32 num_cs = 1;
 	int status;
 
 	is_lpss_priv = platform_get_resource_byname(pdev, IORESOURCE_MEM, "lpss_priv");
@@ -1395,8 +1353,11 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
 		pdata->dma_filter = pxa2xx_spi_idma_filter;
 	}
 
+	/* Read number of chip select pins, if provided */
+	device_property_read_u32(dev, "num-cs", &num_cs);
+
+	pdata->num_chipselect = num_cs;
 	pdata->is_target = device_property_read_bool(dev, "spi-slave");
-	pdata->num_chipselect = 1;
 	pdata->enable_dma = true;
 	pdata->dma_burst_size = 1;
 
@@ -1457,6 +1418,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 		if (IS_ERR(platform_info))
 			return dev_err_probe(dev, PTR_ERR(platform_info), "missing platform data\n");
 	}
+	dev_dbg(dev, "DMA burst size set to %u\n", platform_info->dma_burst_size);
 
 	ssp = pxa_ssp_request(pdev->id, pdev->name);
 	if (!ssp)
diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h
index 45cdbbc71c4b..93e1e471e1c6 100644
--- a/drivers/spi/spi-pxa2xx.h
+++ b/drivers/spi/spi-pxa2xx.h
@@ -7,15 +7,34 @@
 #ifndef SPI_PXA2XX_H
 #define SPI_PXA2XX_H
 
-#include <linux/interrupt.h>
-#include <linux/io.h>
+#include <linux/dmaengine.h>
+#include <linux/irqreturn.h>
 #include <linux/types.h>
 #include <linux/sizes.h>
 
 #include <linux/pxa2xx_ssp.h>
 
 struct gpio_desc;
-struct pxa2xx_spi_controller;
+
+/*
+ * The platform data for SSP controller devices
+ * (resides in device.platform_data).
+ */
+struct pxa2xx_spi_controller {
+	u8 num_chipselect;
+	u8 enable_dma;
+	u8 dma_burst_size;
+	bool is_target;
+
+	/* DMA engine specific config */
+	dma_filter_fn dma_filter;
+	void *tx_param;
+	void *rx_param;
+
+	/* For non-PXA arches */
+	struct ssp_device ssp;
+};
+
 struct spi_controller;
 struct spi_device;
 struct spi_transfer;
@@ -56,18 +75,6 @@ struct driver_data {
 	struct gpio_desc *gpiod_ready;
 };
 
-struct chip_data {
-	u32 cr1;
-	u32 dds_rate;
-	u32 timeout;
-	u8 enable_dma;
-	u32 dma_burst_size;
-	u32 dma_threshold;
-	u32 threshold;
-	u16 lpss_rx_threshold;
-	u16 lpss_tx_threshold;
-};
-
 static inline u32 pxa2xx_spi_read(const struct driver_data *drv_data, u32 reg)
 {
 	return pxa_ssp_read_reg(drv_data->ssp, reg);
@@ -123,10 +130,5 @@ extern void pxa2xx_spi_dma_start(struct driver_data *drv_data);
 extern void pxa2xx_spi_dma_stop(struct driver_data *drv_data);
 extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data);
 extern void pxa2xx_spi_dma_release(struct driver_data *drv_data);
-extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
-						  struct spi_device *spi,
-						  u8 bits_per_word,
-						  u32 *burst_code,
-						  u32 *threshold);
 
 #endif /* SPI_PXA2XX_H */