diff options
Diffstat (limited to 'drivers/spi/spi-oc-tiny.c')
| -rw-r--r-- | drivers/spi/spi-oc-tiny.c | 192 |
1 files changed, 42 insertions, 150 deletions
diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c index 58deb79d046b..cba229920357 100644 --- a/drivers/spi/spi-oc-tiny.c +++ b/drivers/spi/spi-oc-tiny.c @@ -1,7 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0-only /* - * OpenCores tiny SPI master driver + * OpenCores tiny SPI host driver * - * http://opencores.org/project,tiny_spi + * https://opencores.org/project,tiny_spi * * Copyright (C) 2011 Thomas Chou <thomas@wytron.com.tw> * @@ -9,13 +10,8 @@ * Copyright (c) 2006 Ben Dooks * Copyright (c) 2006 Simtec Electronics * Ben Dooks <ben@simtec.co.uk> - * - * 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. */ -#include <linux/init.h> #include <linux/interrupt.h> #include <linux/errno.h> #include <linux/module.h> @@ -24,7 +20,6 @@ #include <linux/spi/spi_bitbang.h> #include <linux/spi/spi_oc_tiny.h> #include <linux/io.h> -#include <linux/gpio.h> #include <linux/of.h> #define DRV_NAME "spi_oc_tiny" @@ -54,13 +49,11 @@ struct tiny_spi { unsigned int txc, rxc; const u8 *txp; u8 *rxp; - int gpio_cs_count; - int *gpio_cs; }; static inline struct tiny_spi *tiny_spi_to_hw(struct spi_device *sdev) { - return spi_master_get_devdata(sdev->master); + return spi_controller_get_devdata(sdev->controller); } static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz) @@ -70,16 +63,6 @@ static unsigned int tiny_spi_baud(struct spi_device *spi, unsigned int hz) return min(DIV_ROUND_UP(hw->freq, hz * 2), (1U << hw->baudwidth)) - 1; } -static void tiny_spi_chipselect(struct spi_device *spi, int is_active) -{ - struct tiny_spi *hw = tiny_spi_to_hw(spi); - - if (hw->gpio_cs_count > 0) { - gpio_set_value(hw->gpio_cs[spi->chip_select], - (spi->mode & SPI_CS_HIGH) ? is_active : !is_active); - } -} - static int tiny_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { @@ -103,7 +86,7 @@ static int tiny_spi_setup(struct spi_device *spi) hw->speed_hz = spi->max_speed_hz; hw->baud = tiny_spi_baud(spi, hw->speed_hz); } - hw->mode = spi->mode & (SPI_CPOL | SPI_CPHA); + hw->mode = spi->mode & SPI_MODE_X_MASK; return 0; } @@ -153,62 +136,22 @@ static int tiny_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) } wait_for_completion(&hw->done); - } else if (txp && rxp) { - /* we need to tighten the transfer loop */ - writeb(*txp++, hw->base + TINY_SPI_TXDATA); - if (t->len > 1) { - writeb(*txp++, hw->base + TINY_SPI_TXDATA); - for (i = 2; i < t->len; i++) { - u8 rx, tx = *txp++; - tiny_spi_wait_txr(hw); - rx = readb(hw->base + TINY_SPI_TXDATA); - writeb(tx, hw->base + TINY_SPI_TXDATA); - *rxp++ = rx; - } - tiny_spi_wait_txr(hw); - *rxp++ = readb(hw->base + TINY_SPI_TXDATA); - } - tiny_spi_wait_txe(hw); - *rxp++ = readb(hw->base + TINY_SPI_RXDATA); - } else if (rxp) { - writeb(0, hw->base + TINY_SPI_TXDATA); - if (t->len > 1) { - writeb(0, - hw->base + TINY_SPI_TXDATA); - for (i = 2; i < t->len; i++) { - u8 rx; - tiny_spi_wait_txr(hw); - rx = readb(hw->base + TINY_SPI_TXDATA); - writeb(0, hw->base + TINY_SPI_TXDATA); - *rxp++ = rx; - } - tiny_spi_wait_txr(hw); - *rxp++ = readb(hw->base + TINY_SPI_TXDATA); - } - tiny_spi_wait_txe(hw); - *rxp++ = readb(hw->base + TINY_SPI_RXDATA); - } else if (txp) { - writeb(*txp++, hw->base + TINY_SPI_TXDATA); - if (t->len > 1) { - writeb(*txp++, hw->base + TINY_SPI_TXDATA); - for (i = 2; i < t->len; i++) { - u8 tx = *txp++; - tiny_spi_wait_txr(hw); - writeb(tx, hw->base + TINY_SPI_TXDATA); - } - } - tiny_spi_wait_txe(hw); } else { - writeb(0, hw->base + TINY_SPI_TXDATA); - if (t->len > 1) { - writeb(0, hw->base + TINY_SPI_TXDATA); - for (i = 2; i < t->len; i++) { + /* we need to tighten the transfer loop */ + writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA); + for (i = 1; i < t->len; i++) { + writeb(txp ? *txp++ : 0, hw->base + TINY_SPI_TXDATA); + + if (rxp || (i != t->len - 1)) tiny_spi_wait_txr(hw); - writeb(0, hw->base + TINY_SPI_TXDATA); - } + if (rxp) + *rxp++ = readb(hw->base + TINY_SPI_TXDATA); } tiny_spi_wait_txe(hw); + if (rxp) + *rxp++ = readb(hw->base + TINY_SPI_RXDATA); } + return t->len; } @@ -241,39 +184,19 @@ static irqreturn_t tiny_spi_irq(int irq, void *dev) } #ifdef CONFIG_OF -#include <linux/of_gpio.h> - static int tiny_spi_of_probe(struct platform_device *pdev) { struct tiny_spi *hw = platform_get_drvdata(pdev); struct device_node *np = pdev->dev.of_node; - unsigned int i; - const __be32 *val; - int len; + u32 val; if (!np) return 0; - hw->gpio_cs_count = of_gpio_count(np); - if (hw->gpio_cs_count > 0) { - hw->gpio_cs = devm_kzalloc(&pdev->dev, - hw->gpio_cs_count * sizeof(unsigned int), - GFP_KERNEL); - if (!hw->gpio_cs) - return -ENOMEM; - } - for (i = 0; i < hw->gpio_cs_count; i++) { - hw->gpio_cs[i] = of_get_gpio_flags(np, i, NULL); - if (hw->gpio_cs[i] < 0) - return -ENODEV; - } - hw->bitbang.master->dev.of_node = pdev->dev.of_node; - val = of_get_property(pdev->dev.of_node, - "clock-frequency", &len); - if (val && len >= sizeof(__be32)) - hw->freq = be32_to_cpup(val); - val = of_get_property(pdev->dev.of_node, "baud-width", &len); - if (val && len >= sizeof(__be32)) - hw->baudwidth = be32_to_cpup(val); + hw->bitbang.ctlr->dev.of_node = pdev->dev.of_node; + if (!of_property_read_u32(np, "clock-frequency", &val)) + hw->freq = val; + if (!of_property_read_u32(np, "baud-width", &val)) + hw->baudwidth = val; return 0; } #else /* !CONFIG_OF */ @@ -285,45 +208,35 @@ static int tiny_spi_of_probe(struct platform_device *pdev) static int tiny_spi_probe(struct platform_device *pdev) { - struct tiny_spi_platform_data *platp = pdev->dev.platform_data; + struct tiny_spi_platform_data *platp = dev_get_platdata(&pdev->dev); struct tiny_spi *hw; - struct spi_master *master; - struct resource *res; - unsigned int i; + struct spi_controller *host; int err = -ENODEV; - master = spi_alloc_master(&pdev->dev, sizeof(struct tiny_spi)); - if (!master) + host = spi_alloc_host(&pdev->dev, sizeof(struct tiny_spi)); + if (!host) return err; - /* setup the master state. */ - master->bus_num = pdev->id; - master->num_chipselect = 255; - master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; - master->setup = tiny_spi_setup; + /* setup the host state. */ + host->bus_num = pdev->id; + host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + host->setup = tiny_spi_setup; + host->use_gpio_descriptors = true; - hw = spi_master_get_devdata(master); + hw = spi_controller_get_devdata(host); platform_set_drvdata(pdev, hw); /* setup the state for the bitbang driver */ - hw->bitbang.master = spi_master_get(master); - if (!hw->bitbang.master) - return err; + hw->bitbang.ctlr = host; hw->bitbang.setup_transfer = tiny_spi_setup_transfer; - hw->bitbang.chipselect = tiny_spi_chipselect; hw->bitbang.txrx_bufs = tiny_spi_txrx_bufs; /* 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; + hw->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(hw->base)) { + err = PTR_ERR(hw->base); + goto exit; + } /* irq is optional */ hw->irq = platform_get_irq(pdev, 0); if (hw->irq >= 0) { @@ -335,10 +248,6 @@ static int tiny_spi_probe(struct platform_device *pdev) } /* find platform data */ if (platp) { - hw->gpio_cs_count = platp->gpio_cs_count; - hw->gpio_cs = platp->gpio_cs; - if (platp->gpio_cs_count && !platp->gpio_cs) - goto exit_busy; hw->freq = platp->freq; hw->baudwidth = platp->baudwidth; } else { @@ -346,13 +255,6 @@ static int tiny_spi_probe(struct platform_device *pdev) if (err) goto exit; } - for (i = 0; i < hw->gpio_cs_count; i++) { - err = gpio_request(hw->gpio_cs[i], dev_name(&pdev->dev)); - if (err) - goto exit_gpio; - gpio_direction_output(hw->gpio_cs[i], 1); - } - hw->bitbang.master->num_chipselect = max(1, hw->gpio_cs_count); /* register our spi controller */ err = spi_bitbang_start(&hw->bitbang); @@ -362,27 +264,18 @@ static int tiny_spi_probe(struct platform_device *pdev) return 0; -exit_gpio: - while (i-- > 0) - gpio_free(hw->gpio_cs[i]); -exit_busy: - err = -EBUSY; exit: - spi_master_put(master); + spi_controller_put(host); return err; } -static int tiny_spi_remove(struct platform_device *pdev) +static void tiny_spi_remove(struct platform_device *pdev) { struct tiny_spi *hw = platform_get_drvdata(pdev); - struct spi_master *master = hw->bitbang.master; - unsigned int i; + struct spi_controller *host = hw->bitbang.ctlr; spi_bitbang_stop(&hw->bitbang); - for (i = 0; i < hw->gpio_cs_count; i++) - gpio_free(hw->gpio_cs[i]); - spi_master_put(master); - return 0; + spi_controller_put(host); } #ifdef CONFIG_OF @@ -398,7 +291,6 @@ static struct platform_driver tiny_spi_driver = { .remove = tiny_spi_remove, .driver = { .name = DRV_NAME, - .owner = THIS_MODULE, .pm = NULL, .of_match_table = of_match_ptr(tiny_spi_match), }, |
