Adding upstream version 6.7.7.upstream/6.7.7

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 36 insertions, 33 deletions

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index e7bb271467..e709887eb2 100644
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -11,6 +11,7 @@
  * spi-atmel.c, Copyright (C) 2006 Atmel Corporation
  */
 
+#include <linux/cleanup.h>
 #include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/debugfs.h>
@@ -26,9 +27,10 @@
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/gpio/consumer.h>
-#include <linux/gpio/machine.h> /* FIXME: using chip internals */
-#include <linux/gpio/driver.h> /* FIXME: using chip internals */
+#include <linux/gpio/machine.h> /* FIXME: using GPIO lookup tables */
 #include <linux/of_irq.h>
+#include <linux/overflow.h>
+#include <linux/slab.h>
 #include <linux/spi/spi.h>
 
 /* SPI register offsets */
@@ -83,6 +85,7 @@ MODULE_PARM_DESC(polling_limit_us,
  * struct bcm2835_spi - BCM2835 SPI controller
  * @regs: base address of register map
  * @clk: core clock, divided to calculate serial clock
+ * @cs_gpio: chip-select GPIO descriptor
  * @clk_hz: core clock cached speed
  * @irq: interrupt, signals TX FIFO empty or RX FIFO ¾ full
  * @tfr: SPI transfer currently processed
@@ -117,6 +120,7 @@ MODULE_PARM_DESC(polling_limit_us,
 struct bcm2835_spi {
 	void __iomem *regs;
 	struct clk *clk;
+	struct gpio_desc *cs_gpio;
 	unsigned long clk_hz;
 	int irq;
 	struct spi_transfer *tfr;
@@ -1156,15 +1160,11 @@ static void bcm2835_spi_handle_err(struct spi_controller *ctlr,
 	bcm2835_spi_reset_hw(bs);
 }
 
-static int chip_match_name(struct gpio_chip *chip, void *data)
-{
-	return !strcmp(chip->label, data);
-}
-
 static void bcm2835_spi_cleanup(struct spi_device *spi)
 {
 	struct bcm2835_spidev *target = spi_get_ctldata(spi);
 	struct spi_controller *ctlr = spi->controller;
+	struct bcm2835_spi *bs = spi_controller_get_devdata(ctlr);
 
 	if (target->clear_rx_desc)
 		dmaengine_desc_free(target->clear_rx_desc);
@@ -1175,6 +1175,9 @@ static void bcm2835_spi_cleanup(struct spi_device *spi)
 				 sizeof(u32),
 				 DMA_TO_DEVICE);
 
+	gpiod_put(bs->cs_gpio);
+	spi_set_csgpiod(spi, 0, NULL);
+
 	kfree(target);
 }
 
@@ -1221,7 +1224,7 @@ static int bcm2835_spi_setup(struct spi_device *spi)
 	struct spi_controller *ctlr = spi->controller;
 	struct bcm2835_spi *bs = spi_controller_get_devdata(ctlr);
 	struct bcm2835_spidev *target = spi_get_ctldata(spi);
-	struct gpio_chip *chip;
+	struct gpiod_lookup_table *lookup __free(kfree) = NULL;
 	int ret;
 	u32 cs;
 
@@ -1288,29 +1291,36 @@ static int bcm2835_spi_setup(struct spi_device *spi)
 	}
 
 	/*
-	 * Translate native CS to GPIO
+	 * TODO: The code below is a slightly better alternative to the utter
+	 * abuse of the GPIO API that I found here before. It creates a
+	 * temporary lookup table, assigns it to the SPI device, gets the GPIO
+	 * descriptor and then releases the lookup table.
 	 *
-	 * FIXME: poking around in the gpiolib internals like this is
-	 * not very good practice. Find a way to locate the real problem
-	 * and fix it. Why is the GPIO descriptor in spi->cs_gpiod
-	 * sometimes not assigned correctly? Erroneous device trees?
+	 * More on the problem that it addresses:
+	 *   https://www.spinics.net/lists/linux-gpio/msg36218.html
 	 */
+	lookup = kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
+	if (!lookup) {
+		ret = -ENOMEM;
+		goto err_cleanup;
+	}
 
-	/* get the gpio chip for the base */
-	chip = gpiochip_find("pinctrl-bcm2835", chip_match_name);
-	if (!chip)
-		return 0;
+	lookup->dev_id = dev_name(&spi->dev);
+	lookup->table[0] = GPIO_LOOKUP("pinctrl-bcm2835",
+				       8 - (spi_get_chipselect(spi, 0)),
+				       "cs", GPIO_LOOKUP_FLAGS_DEFAULT);
+
+	gpiod_add_lookup_table(lookup);
 
-	spi_set_csgpiod(spi, 0, gpiochip_request_own_desc(chip,
-							  8 - (spi_get_chipselect(spi, 0)),
-							  DRV_NAME,
-							  GPIO_LOOKUP_FLAGS_DEFAULT,
-							  GPIOD_OUT_LOW));
-	if (IS_ERR(spi_get_csgpiod(spi, 0))) {
-		ret = PTR_ERR(spi_get_csgpiod(spi, 0));
+	bs->cs_gpio = gpiod_get(&spi->dev, "cs", GPIOD_OUT_LOW);
+	gpiod_remove_lookup_table(lookup);
+	if (IS_ERR(bs->cs_gpio)) {
+		ret = PTR_ERR(bs->cs_gpio);
 		goto err_cleanup;
 	}
 
+	spi_set_csgpiod(spi, 0, bs->cs_gpio);
+
 	/* and set up the "mode" and level */
 	dev_info(&spi->dev, "setting up native-CS%i to use GPIO\n",
 		 spi_get_chipselect(spi, 0));
@@ -1352,7 +1362,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
 	if (IS_ERR(bs->regs))
 		return PTR_ERR(bs->regs);
 
-	bs->clk = devm_clk_get(&pdev->dev, NULL);
+	bs->clk = devm_clk_get_enabled(&pdev->dev, NULL);
 	if (IS_ERR(bs->clk))
 		return dev_err_probe(&pdev->dev, PTR_ERR(bs->clk),
 				     "could not get clk\n");
@@ -1363,14 +1373,11 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
 	if (bs->irq < 0)
 		return bs->irq;
 
-	err = clk_prepare_enable(bs->clk);
-	if (err)
-		return err;
 	bs->clk_hz = clk_get_rate(bs->clk);
 
 	err = bcm2835_dma_init(ctlr, &pdev->dev, bs);
 	if (err)
-		goto out_clk_disable;
+		return err;
 
 	/* initialise the hardware with the default polarities */
 	bcm2835_wr(bs, BCM2835_SPI_CS,
@@ -1396,8 +1403,6 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
 
 out_dma_release:
 	bcm2835_dma_release(ctlr, bs);
-out_clk_disable:
-	clk_disable_unprepare(bs->clk);
 	return err;
 }
 
@@ -1415,8 +1420,6 @@ static void bcm2835_spi_remove(struct platform_device *pdev)
 	/* Clear FIFOs, and disable the HW block */
 	bcm2835_wr(bs, BCM2835_SPI_CS,
 		   BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX);
-
-	clk_disable_unprepare(bs->clk);
 }
 
 static const struct of_device_id bcm2835_spi_match[] = {