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 | 11 | #include <linux/module.h> |
b0ceb621 | 12 | #include <linux/of.h> |
161b96c3 AS |
13 | #include <linux/interrupt.h> |
14 | #include <linux/platform_device.h> | |
3dc92594 AS |
15 | #include <linux/regmap.h> |
16 | #include <linux/mfd/syscon.h> | |
17 | #include <linux/mfd/syscon/clps711x.h> | |
161b96c3 | 18 | #include <linux/spi/spi.h> |
161b96c3 | 19 | |
6acaadc8 | 20 | #define DRIVER_NAME "clps711x-spi" |
161b96c3 | 21 | |
3dc92594 AS |
22 | #define SYNCIO_FRMLEN(x) ((x) << 8) |
23 | #define SYNCIO_TXFRMEN (1 << 14) | |
24 | ||
161b96c3 | 25 | struct spi_clps711x_data { |
3dc92594 AS |
26 | void __iomem *syncio; |
27 | struct regmap *syscon; | |
161b96c3 | 28 | struct clk *spi_clk; |
161b96c3 AS |
29 | |
30 | u8 *tx_buf; | |
31 | u8 *rx_buf; | |
8dda9d9a | 32 | unsigned int bpw; |
161b96c3 | 33 | int len; |
161b96c3 AS |
34 | }; |
35 | ||
bf5c2e27 AL |
36 | static int spi_clps711x_prepare_message(struct spi_master *master, |
37 | struct spi_message *msg) | |
161b96c3 | 38 | { |
3dc92594 | 39 | struct spi_clps711x_data *hw = spi_master_get_devdata(master); |
8dda9d9a | 40 | struct spi_device *spi = msg->spi; |
161b96c3 | 41 | |
3dc92594 AS |
42 | /* Setup mode for transfer */ |
43 | return regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCKNSEN, | |
44 | (spi->mode & SPI_CPHA) ? | |
45 | SYSCON3_ADCCKNSEN : 0); | |
bf5c2e27 | 46 | } |
161b96c3 | 47 | |
bf5c2e27 AL |
48 | static int spi_clps711x_transfer_one(struct spi_master *master, |
49 | struct spi_device *spi, | |
50 | struct spi_transfer *xfer) | |
51 | { | |
52 | struct spi_clps711x_data *hw = spi_master_get_devdata(master); | |
53 | u8 data; | |
161b96c3 | 54 | |
a5b4b234 | 55 | clk_set_rate(hw->spi_clk, xfer->speed_hz ? : spi->max_speed_hz); |
161b96c3 | 56 | |
bf5c2e27 | 57 | hw->len = xfer->len; |
bed890b4 | 58 | hw->bpw = xfer->bits_per_word; |
bf5c2e27 AL |
59 | hw->tx_buf = (u8 *)xfer->tx_buf; |
60 | hw->rx_buf = (u8 *)xfer->rx_buf; | |
161b96c3 | 61 | |
bf5c2e27 AL |
62 | /* Initiate transfer */ |
63 | data = hw->tx_buf ? *hw->tx_buf++ : 0; | |
3dc92594 AS |
64 | writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN, hw->syncio); |
65 | ||
bf5c2e27 | 66 | return 1; |
161b96c3 AS |
67 | } |
68 | ||
69 | static irqreturn_t spi_clps711x_isr(int irq, void *dev_id) | |
70 | { | |
bf5c2e27 AL |
71 | struct spi_master *master = dev_id; |
72 | struct spi_clps711x_data *hw = spi_master_get_devdata(master); | |
c7a26f12 | 73 | u8 data; |
161b96c3 AS |
74 | |
75 | /* Handle RX */ | |
3dc92594 | 76 | data = readb(hw->syncio); |
161b96c3 | 77 | if (hw->rx_buf) |
c7a26f12 | 78 | *hw->rx_buf++ = data; |
161b96c3 AS |
79 | |
80 | /* Handle TX */ | |
c7a26f12 AS |
81 | if (--hw->len > 0) { |
82 | data = hw->tx_buf ? *hw->tx_buf++ : 0; | |
3dc92594 AS |
83 | writel(data | SYNCIO_FRMLEN(hw->bpw) | SYNCIO_TXFRMEN, |
84 | hw->syncio); | |
161b96c3 | 85 | } else |
bf5c2e27 | 86 | spi_finalize_current_transfer(master); |
161b96c3 AS |
87 | |
88 | return IRQ_HANDLED; | |
89 | } | |
90 | ||
fd4a319b | 91 | static int spi_clps711x_probe(struct platform_device *pdev) |
161b96c3 | 92 | { |
b0ceb621 | 93 | struct device_node *np = pdev->dev.of_node; |
161b96c3 | 94 | struct spi_clps711x_data *hw; |
3dc92594 | 95 | struct spi_master *master; |
6acaadc8 | 96 | int irq, ret; |
161b96c3 | 97 | |
3dc92594 AS |
98 | irq = platform_get_irq(pdev, 0); |
99 | if (irq < 0) | |
100 | return irq; | |
101 | ||
3e9ea4b4 AS |
102 | master = spi_alloc_master(&pdev->dev, sizeof(*hw)); |
103 | if (!master) | |
161b96c3 | 104 | return -ENOMEM; |
3e9ea4b4 | 105 | |
054320b2 | 106 | master->use_gpio_descriptors = true; |
6acaadc8 | 107 | master->bus_num = -1; |
161b96c3 | 108 | master->mode_bits = SPI_CPHA | SPI_CS_HIGH; |
39062411 | 109 | master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 8); |
6acaadc8 | 110 | master->dev.of_node = pdev->dev.of_node; |
bf5c2e27 AL |
111 | master->prepare_message = spi_clps711x_prepare_message; |
112 | master->transfer_one = spi_clps711x_transfer_one; | |
161b96c3 AS |
113 | |
114 | hw = spi_master_get_devdata(master); | |
115 | ||
a5b4b234 | 116 | hw->spi_clk = devm_clk_get(&pdev->dev, NULL); |
161b96c3 | 117 | if (IS_ERR(hw->spi_clk)) { |
161b96c3 AS |
118 | ret = PTR_ERR(hw->spi_clk); |
119 | goto err_out; | |
120 | } | |
161b96c3 | 121 | |
b0ceb621 | 122 | hw->syscon = syscon_regmap_lookup_by_phandle(np, "syscon"); |
3dc92594 AS |
123 | if (IS_ERR(hw->syscon)) { |
124 | ret = PTR_ERR(hw->syscon); | |
125 | goto err_out; | |
126 | } | |
127 | ||
ae43724d | 128 | hw->syncio = devm_platform_ioremap_resource(pdev, 0); |
3dc92594 AS |
129 | if (IS_ERR(hw->syncio)) { |
130 | ret = PTR_ERR(hw->syncio); | |
131 | goto err_out; | |
132 | } | |
133 | ||
161b96c3 | 134 | /* Disable extended mode due hardware problems */ |
3dc92594 | 135 | regmap_update_bits(hw->syscon, SYSCON_OFFSET, SYSCON3_ADCCON, 0); |
161b96c3 AS |
136 | |
137 | /* Clear possible pending interrupt */ | |
3dc92594 | 138 | readl(hw->syncio); |
161b96c3 | 139 | |
3dc92594 | 140 | ret = devm_request_irq(&pdev->dev, irq, spi_clps711x_isr, 0, |
bf5c2e27 | 141 | dev_name(&pdev->dev), master); |
3dc92594 | 142 | if (ret) |
c7083790 | 143 | goto err_out; |
161b96c3 | 144 | |
c493fc4b | 145 | ret = devm_spi_register_master(&pdev->dev, master); |
6acaadc8 | 146 | if (!ret) |
161b96c3 | 147 | return 0; |
161b96c3 | 148 | |
161b96c3 | 149 | err_out: |
161b96c3 | 150 | spi_master_put(master); |
161b96c3 AS |
151 | |
152 | return ret; | |
153 | } | |
154 | ||
6acaadc8 AS |
155 | static const struct of_device_id clps711x_spi_dt_ids[] = { |
156 | { .compatible = "cirrus,ep7209-spi", }, | |
157 | { } | |
158 | }; | |
159 | MODULE_DEVICE_TABLE(of, clps711x_spi_dt_ids); | |
160 | ||
161b96c3 AS |
161 | static struct platform_driver clps711x_spi_driver = { |
162 | .driver = { | |
163 | .name = DRIVER_NAME, | |
6acaadc8 | 164 | .of_match_table = clps711x_spi_dt_ids, |
161b96c3 AS |
165 | }, |
166 | .probe = spi_clps711x_probe, | |
161b96c3 AS |
167 | }; |
168 | module_platform_driver(clps711x_spi_driver); | |
169 | ||
170 | MODULE_LICENSE("GPL"); | |
171 | MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>"); | |
172 | MODULE_DESCRIPTION("CLPS711X SPI bus driver"); | |
350a9b33 | 173 | MODULE_ALIAS("platform:" DRIVER_NAME); |