[linux-2.6-block.git] / drivers / spi / spi-clps711x.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  CLPS711X SPI bus driver
 *
 *  Copyright (C) 2012-2016 Alexander Shiyan <shc_work@mail.ru>
 */

#include <linux/io.h>
#include <linux/clk.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/clps711x.h>
#include <linux/spi/spi.h>

#define DRIVER_NAME		"clps711x-spi"

#define SYNCIO_FRMLEN(x)	((x) << 8)
#define SYNCIO_TXFRMEN		(1 << 14)

struct spi_clps711x_data {
	void __iomem		*syncio;
	struct regmap		*syscon;
	struct clk		*spi_clk;

	u8			*tx_buf;
	u8			*rx_buf;
	unsigned int		bpw;
	int			len;
};

static int spi_clps711x_prepare_message(struct spi_master *master,
					struct spi_message *msg)
{
	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
	struct spi_device *spi = msg->spi;

	/* Setup mode for transfer */
	return regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCKNSEN,
				  (spi->mode & SPI_CPHA) ?
				  SYSCON3_ADCCKNSEN : 0);
}

static int spi_clps711x_transfer_one(struct spi_master *master,
				     struct spi_device *spi,
				     struct spi_transfer *xfer)
{
	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
	u8 data;

	clk_set_rate(hw->spi_clk, xfer->speed_hz ? : spi->max_speed_hz);

	hw->len = xfer->len;
	hw->bpw = xfer->bits_per_word;
	hw->tx_buf = (u8 *)xfer->tx_buf;
	hw->rx_buf = (u8 *)xfer->rx_buf;

	/* Initiate transfer */
	data = hw->tx_buf ? *hw->tx_buf++ : 0;
	writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN, hw->syncio);

	return 1;
}

static irqreturn_t spi_clps711x_isr(int irq, void *dev_id)
{
	struct spi_master *master = dev_id;
	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
	u8 data;

	/* Handle RX */
	data = readb(hw->syncio);
	if (hw->rx_buf)
		*hw->rx_buf++ = data;

	/* Handle TX */
	if (--hw->len > 0) {
		data = hw->tx_buf ? *hw->tx_buf++ : 0;
		writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN,
		       hw->syncio);
	} else
		spi_finalize_current_transfer(master);

	return IRQ_HANDLED;
}

static int spi_clps711x_probe(struct platform_device *pdev)
{
	struct spi_clps711x_data *hw;
	struct spi_master *master;
	struct resource *res;
	int irq, ret;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return irq;

	master = spi_alloc_master(&pdev->dev, sizeof(*hw));
	if (!master)
		return -ENOMEM;

	master->use_gpio_descriptors = true;
	master->bus_num = -1;
	master->mode_bits = SPI_CPHA | SPI_CS_HIGH;
	master->bits_per_word_mask =  SPI_BPW_RANGE_MASK(1, 8);
	master->dev.of_node = pdev->dev.of_node;
	master->prepare_message = spi_clps711x_prepare_message;
	master->transfer_one = spi_clps711x_transfer_one;

	hw = spi_master_get_devdata(master);

	hw->spi_clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(hw->spi_clk)) {
		ret = PTR_ERR(hw->spi_clk);
		goto err_out;
	}

	hw->syscon =
		syscon_regmap_lookup_by_compatible("cirrus,ep7209-syscon3");
	if (IS_ERR(hw->syscon)) {
		ret = PTR_ERR(hw->syscon);
		goto err_out;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	hw->syncio = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(hw->syncio)) {
		ret = PTR_ERR(hw->syncio);
		goto err_out;
	}

	/* Disable extended mode due hardware problems */
	regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCON, 0);

	/* Clear possible pending interrupt */
	readl(hw->syncio);

	ret = devm_request_irq(&pdev->dev, irq, spi_clps711x_isr, 0,
			       dev_name(&pdev->dev), master);
	if (ret)
		goto err_out;

	ret = devm_spi_register_master(&pdev->dev, master);
	if (!ret)
		return 0;

err_out:
	spi_master_put(master);

	return ret;
}

static const struct of_device_id clps711x_spi_dt_ids[] = {
	{ .compatible = "cirrus,ep7209-spi", },
	{ }
};
MODULE_DEVICE_TABLE(of, clps711x_spi_dt_ids);

static struct platform_driver clps711x_spi_driver = {
	.driver	= {
		.name	= DRIVER_NAME,
		.of_match_table = clps711x_spi_dt_ids,
	},
	.probe	= spi_clps711x_probe,
};
module_platform_driver(clps711x_spi_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
MODULE_DESCRIPTION("CLPS711X SPI bus driver");
MODULE_ALIAS("platform:" DRIVER_NAME);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
161b96c3 AS	2	/*
	3	* CLPS711X SPI bus driver
	4	*
6acaadc8	5	* Copyright (C) 2012-2016 Alexander Shiyan <shc_work@mail.ru>
161b96c3 AS	6	*/
	7
	8	#include <linux/io.h>
	9	#include <linux/clk.h>
054320b2	10	#include <linux/gpio/consumer.h>
161b96c3 AS	11	#include <linux/module.h>
	12	#include <linux/interrupt.h>
	13	#include <linux/platform_device.h>
3dc92594 AS	14	#include <linux/regmap.h>
	15	#include <linux/mfd/syscon.h>
	16	#include <linux/mfd/syscon/clps711x.h>
161b96c3	17	#include <linux/spi/spi.h>
161b96c3	18
6acaadc8	19	#define DRIVER_NAME "clps711x-spi"
161b96c3	20
3dc92594 AS	21	#define SYNCIO_FRMLEN(x) ((x) << 8)
	22	#define SYNCIO_TXFRMEN (1 << 14)
	23
161b96c3	24	struct spi_clps711x_data {
3dc92594 AS	25	void __iomem *syncio;
3dc92594 AS	26	struct regmap *syscon;
161b96c3	27	struct clk *spi_clk;
161b96c3 AS	28
	29	u8 *tx_buf;
	30	u8 *rx_buf;
8dda9d9a	31	unsigned int bpw;
161b96c3	32	int len;
161b96c3 AS	33	};
161b96c3 AS	34
bf5c2e27 AL	35	static int spi_clps711x_prepare_message(struct spi_master *master,
bf5c2e27 AL	36	struct spi_message *msg)
161b96c3	37	{
3dc92594	38	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
8dda9d9a	39	struct spi_device *spi = msg->spi;
161b96c3	40
3dc92594 AS	41	/* Setup mode for transfer */
	42	return regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCKNSEN,
	43	(spi->mode & SPI_CPHA) ?
	44	SYSCON3_ADCCKNSEN : 0);
bf5c2e27	45	}
161b96c3	46
bf5c2e27 AL	47	static int spi_clps711x_transfer_one(struct spi_master *master,
	48	struct spi_device *spi,
	49	struct spi_transfer *xfer)
	50	{
	51	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
	52	u8 data;
161b96c3	53
a5b4b234	54	clk_set_rate(hw->spi_clk, xfer->speed_hz ? : spi->max_speed_hz);
161b96c3	55
bf5c2e27	56	hw->len = xfer->len;
bed890b4	57	hw->bpw = xfer->bits_per_word;
bf5c2e27 AL	58	hw->tx_buf = (u8 *)xfer->tx_buf;
bf5c2e27 AL	59	hw->rx_buf = (u8 *)xfer->rx_buf;
161b96c3	60
bf5c2e27 AL	61	/* Initiate transfer */
bf5c2e27 AL	62	data = hw->tx_buf ? *hw->tx_buf++ : 0;
3dc92594 AS	63	writel(data \| SYNCIO_FRMLEN(hw->bpw) \| SYNCIO_TXFRMEN, hw->syncio);
3dc92594 AS	64
bf5c2e27	65	return 1;
161b96c3 AS	66	}
	67
	68	static irqreturn_t spi_clps711x_isr(int irq, void *dev_id)
	69	{
bf5c2e27 AL	70	struct spi_master *master = dev_id;
bf5c2e27 AL	71	struct spi_clps711x_data *hw = spi_master_get_devdata(master);
c7a26f12	72	u8 data;
161b96c3 AS	73
161b96c3 AS	74	/* Handle RX */
3dc92594	75	data = readb(hw->syncio);
161b96c3	76	if (hw->rx_buf)
c7a26f12	77	*hw->rx_buf++ = data;
161b96c3 AS	78
161b96c3 AS	79	/* Handle TX */
c7a26f12 AS	80	if (--hw->len > 0) {
c7a26f12 AS	81	data = hw->tx_buf ? *hw->tx_buf++ : 0;
3dc92594 AS	82	writel(data \| SYNCIO_FRMLEN(hw->bpw) \| SYNCIO_TXFRMEN,
3dc92594 AS	83	hw->syncio);
161b96c3	84	} else
bf5c2e27	85	spi_finalize_current_transfer(master);
161b96c3 AS	86
	87	return IRQ_HANDLED;
	88	}
	89
fd4a319b	90	static int spi_clps711x_probe(struct platform_device *pdev)
161b96c3	91	{
161b96c3	92	struct spi_clps711x_data *hw;
3dc92594 AS	93	struct spi_master *master;
3dc92594 AS	94	struct resource *res;
6acaadc8	95	int irq, ret;
161b96c3	96
3dc92594 AS	97	irq = platform_get_irq(pdev, 0);
	98	if (irq < 0)
	99	return irq;
	100
3e9ea4b4 AS	101	master = spi_alloc_master(&pdev->dev, sizeof(*hw));
3e9ea4b4 AS	102	if (!master)
161b96c3	103	return -ENOMEM;
3e9ea4b4	104
054320b2	105	master->use_gpio_descriptors = true;
6acaadc8	106	master->bus_num = -1;
161b96c3	107	master->mode_bits = SPI_CPHA \| SPI_CS_HIGH;
8dda9d9a	108	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 8);
6acaadc8	109	master->dev.of_node = pdev->dev.of_node;
bf5c2e27 AL	110	master->prepare_message = spi_clps711x_prepare_message;
bf5c2e27 AL	111	master->transfer_one = spi_clps711x_transfer_one;
161b96c3 AS	112
	113	hw = spi_master_get_devdata(master);
	114
a5b4b234	115	hw->spi_clk = devm_clk_get(&pdev->dev, NULL);
161b96c3	116	if (IS_ERR(hw->spi_clk)) {
161b96c3 AS	117	ret = PTR_ERR(hw->spi_clk);
	118	goto err_out;
	119	}
161b96c3	120
6acaadc8 AS	121	hw->syscon =
6acaadc8 AS	122	syscon_regmap_lookup_by_compatible("cirrus,ep7209-syscon3");
3dc92594 AS	123	if (IS_ERR(hw->syscon)) {
	124	ret = PTR_ERR(hw->syscon);
	125	goto err_out;
	126	}
	127
3dc92594 AS	128	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	129	hw->syncio = devm_ioremap_resource(&pdev->dev, res);
	130	if (IS_ERR(hw->syncio)) {
	131	ret = PTR_ERR(hw->syncio);
	132	goto err_out;
	133	}
	134
161b96c3	135	/* Disable extended mode due hardware problems */
3dc92594	136	regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCON, 0);
161b96c3 AS	137
161b96c3 AS	138	/* Clear possible pending interrupt */
3dc92594	139	readl(hw->syncio);
161b96c3	140
3dc92594	141	ret = devm_request_irq(&pdev->dev, irq, spi_clps711x_isr, 0,
bf5c2e27	142	dev_name(&pdev->dev), master);
3dc92594	143	if (ret)
c7083790	144	goto err_out;
161b96c3	145
c493fc4b	146	ret = devm_spi_register_master(&pdev->dev, master);
6acaadc8	147	if (!ret)
161b96c3	148	return 0;
161b96c3	149
161b96c3	150	err_out:
161b96c3	151	spi_master_put(master);
161b96c3 AS	152
	153	return ret;
	154	}
	155
6acaadc8 AS	156	static const struct of_device_id clps711x_spi_dt_ids[] = {
	157	{ .compatible = "cirrus,ep7209-spi", },
	158	{ }
	159	};
	160	MODULE_DEVICE_TABLE(of, clps711x_spi_dt_ids);
	161
161b96c3 AS	162	static struct platform_driver clps711x_spi_driver = {
	163	.driver = {
	164	.name = DRIVER_NAME,
6acaadc8	165	.of_match_table = clps711x_spi_dt_ids,
161b96c3 AS	166	},
161b96c3 AS	167	.probe = spi_clps711x_probe,
161b96c3 AS	168	};
	169	module_platform_driver(clps711x_spi_driver);
	170
	171	MODULE_LICENSE("GPL");
	172	MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
	173	MODULE_DESCRIPTION("CLPS711X SPI bus driver");
350a9b33	174	MODULE_ALIAS("platform:" DRIVER_NAME);