xref: /openbmc/linux/drivers/mmc/host/of_mmc_spi.c (revision 79e790ff)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * OpenFirmware bindings for the MMC-over-SPI driver
4  *
5  * Copyright (c) MontaVista Software, Inc. 2008.
6  *
7  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/slab.h>
14 #include <linux/irq.h>
15 #include <linux/of.h>
16 #include <linux/of_irq.h>
17 #include <linux/spi/spi.h>
18 #include <linux/spi/mmc_spi.h>
19 #include <linux/mmc/core.h>
20 #include <linux/mmc/host.h>
21 
22 MODULE_LICENSE("GPL");
23 
24 struct of_mmc_spi {
25 	int detect_irq;
26 	struct mmc_spi_platform_data pdata;
27 };
28 
29 static struct of_mmc_spi *to_of_mmc_spi(struct device *dev)
30 {
31 	return container_of(dev->platform_data, struct of_mmc_spi, pdata);
32 }
33 
34 static int of_mmc_spi_init(struct device *dev,
35 			   irqreturn_t (*irqhandler)(int, void *), void *mmc)
36 {
37 	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
38 
39 	return request_threaded_irq(oms->detect_irq, NULL, irqhandler,
40 					IRQF_ONESHOT, dev_name(dev), mmc);
41 }
42 
43 static void of_mmc_spi_exit(struct device *dev, void *mmc)
44 {
45 	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
46 
47 	free_irq(oms->detect_irq, mmc);
48 }
49 
50 struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
51 {
52 	struct mmc_host *mmc = dev_get_drvdata(&spi->dev);
53 	struct device *dev = &spi->dev;
54 	struct of_mmc_spi *oms;
55 
56 	if (dev->platform_data || !dev_fwnode(dev))
57 		return dev->platform_data;
58 
59 	oms = kzalloc(sizeof(*oms), GFP_KERNEL);
60 	if (!oms)
61 		return NULL;
62 
63 	if (mmc_of_parse_voltage(mmc, &oms->pdata.ocr_mask) < 0)
64 		goto err_ocr;
65 
66 	oms->detect_irq = spi->irq;
67 	if (oms->detect_irq > 0) {
68 		oms->pdata.init = of_mmc_spi_init;
69 		oms->pdata.exit = of_mmc_spi_exit;
70 	} else {
71 		oms->pdata.caps |= MMC_CAP_NEEDS_POLL;
72 	}
73 
74 	dev->platform_data = &oms->pdata;
75 	return dev->platform_data;
76 err_ocr:
77 	kfree(oms);
78 	return NULL;
79 }
80 EXPORT_SYMBOL(mmc_spi_get_pdata);
81 
82 void mmc_spi_put_pdata(struct spi_device *spi)
83 {
84 	struct device *dev = &spi->dev;
85 	struct of_mmc_spi *oms = to_of_mmc_spi(dev);
86 
87 	if (!dev->platform_data || !dev_fwnode(dev))
88 		return;
89 
90 	kfree(oms);
91 	dev->platform_data = NULL;
92 }
93 EXPORT_SYMBOL(mmc_spi_put_pdata);
94