drivers/mmc/host/of_mmc_spi.c

   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 /* For archs that don't support NO_IRQ (such as mips), provide a dummy value */
  23 #ifndef NO_IRQ
  24 #define NO_IRQ 0
  25 #endif
  26
  27 MODULE_LICENSE("GPL");
  28
  29 struct of_mmc_spi {
  30         int detect_irq;
  31         struct mmc_spi_platform_data pdata;
  32 };
  33
  34 static struct of_mmc_spi *to_of_mmc_spi(struct device *dev)
  35 {
  36         return container_of(dev->platform_data, struct of_mmc_spi, pdata);
  37 }
  38
  39 static int of_mmc_spi_init(struct device *dev,
  40                            irqreturn_t (*irqhandler)(int, void *), void *mmc)
  41 {
  42         struct of_mmc_spi *oms = to_of_mmc_spi(dev);
  43
  44         return request_threaded_irq(oms->detect_irq, NULL, irqhandler,
  45                                         IRQF_ONESHOT, dev_name(dev), mmc);
  46 }
  47
  48 static void of_mmc_spi_exit(struct device *dev, void *mmc)
  49 {
  50         struct of_mmc_spi *oms = to_of_mmc_spi(dev);
  51
  52         free_irq(oms->detect_irq, mmc);
  53 }
  54
  55 struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
  56 {
  57         struct device *dev = &spi->dev;
  58         struct device_node *np = dev->of_node;
  59         struct of_mmc_spi *oms;
  60
  61         if (dev->platform_data || !np)
  62                 return dev->platform_data;
  63
  64         oms = kzalloc(sizeof(*oms), GFP_KERNEL);
  65         if (!oms)
  66                 return NULL;
  67
  68         if (mmc_of_parse_voltage(np, &oms->pdata.ocr_mask) <= 0)
  69                 goto err_ocr;
  70
  71         oms->detect_irq = irq_of_parse_and_map(np, 0);
  72         if (oms->detect_irq != 0) {
  73                 oms->pdata.init = of_mmc_spi_init;
  74                 oms->pdata.exit = of_mmc_spi_exit;
  75         } else {
  76                 oms->pdata.caps |= MMC_CAP_NEEDS_POLL;
  77         }
  78
  79         dev->platform_data = &oms->pdata;
  80         return dev->platform_data;
  81 err_ocr:
  82         kfree(oms);
  83         return NULL;
  84 }
  85 EXPORT_SYMBOL(mmc_spi_get_pdata);
  86
  87 void mmc_spi_put_pdata(struct spi_device *spi)
  88 {
  89         struct device *dev = &spi->dev;
  90         struct device_node *np = dev->of_node;
  91         struct of_mmc_spi *oms = to_of_mmc_spi(dev);
  92
  93         if (!dev->platform_data || !np)
  94                 return;
  95
  96         kfree(oms);
  97         dev->platform_data = NULL;
  98 }
  99 EXPORT_SYMBOL(mmc_spi_put_pdata);