Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux-2.6-microblaze.git] / drivers / mfd / at91-usart.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for AT91 USART
4  *
5  * Copyright (C) 2018 Microchip Technology
6  *
7  * Author: Radu Pirea <radu.pirea@microchip.com>
8  *
9  */
10
11 #include <dt-bindings/mfd/at91-usart.h>
12
13 #include <linux/module.h>
14 #include <linux/mfd/core.h>
15 #include <linux/of.h>
16 #include <linux/property.h>
17
18 static const struct mfd_cell at91_usart_spi_subdev =
19         MFD_CELL_NAME("at91_usart_spi");
20
21 static const struct mfd_cell at91_usart_serial_subdev =
22         MFD_CELL_NAME("atmel_usart_serial");
23
24 static int at91_usart_mode_probe(struct platform_device *pdev)
25 {
26         const struct mfd_cell *cell;
27         u32 opmode = AT91_USART_MODE_SERIAL;
28
29         device_property_read_u32(&pdev->dev, "atmel,usart-mode", &opmode);
30
31         switch (opmode) {
32         case AT91_USART_MODE_SPI:
33                 cell = &at91_usart_spi_subdev;
34                 break;
35         case AT91_USART_MODE_SERIAL:
36                 cell = &at91_usart_serial_subdev;
37                 break;
38         default:
39                 dev_err(&pdev->dev, "atmel,usart-mode has an invalid value %u\n",
40                         opmode);
41                 return -EINVAL;
42         }
43
44         return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, cell, 1,
45                               NULL, 0, NULL);
46 }
47
48 static const struct of_device_id at91_usart_mode_of_match[] = {
49         { .compatible = "atmel,at91rm9200-usart" },
50         { .compatible = "atmel,at91sam9260-usart" },
51         { /* sentinel */ }
52 };
53
54 MODULE_DEVICE_TABLE(of, at91_usart_mode_of_match);
55
56 static struct platform_driver at91_usart_mfd = {
57         .probe  = at91_usart_mode_probe,
58         .driver = {
59                 .name           = "at91_usart_mode",
60                 .of_match_table = at91_usart_mode_of_match,
61         },
62 };
63
64 module_platform_driver(at91_usart_mfd);
65
66 MODULE_AUTHOR("Radu Pirea <radu.pirea@microchip.com>");
67 MODULE_DESCRIPTION("AT91 USART MFD driver");
68 MODULE_LICENSE("GPL v2");