drivers/clk/bcm/clk-bcm2835-aux.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2015 Broadcom
   4  */
   5
   6 #include <linux/clk.h>
   7 #include <linux/clk-provider.h>
   8 #include <linux/module.h>
   9 #include <linux/platform_device.h>
  10 #include <dt-bindings/clock/bcm2835-aux.h>
  11
  12 #define BCM2835_AUXIRQ          0x00
  13 #define BCM2835_AUXENB          0x04
  14
  15 static int bcm2835_aux_clk_probe(struct platform_device *pdev)
  16 {
  17         struct device *dev = &pdev->dev;
  18         struct clk_hw_onecell_data *onecell;
  19         const char *parent;
  20         struct clk *parent_clk;
  21         struct resource *res;
  22         void __iomem *reg, *gate;
  23
  24         parent_clk = devm_clk_get(dev, NULL);
  25         if (IS_ERR(parent_clk))
  26                 return PTR_ERR(parent_clk);
  27         parent = __clk_get_name(parent_clk);
  28
  29         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  30         reg = devm_ioremap_resource(dev, res);
  31         if (IS_ERR(reg))
  32                 return PTR_ERR(reg);
  33
  34         onecell = devm_kmalloc(dev,
  35                                struct_size(onecell, hws,
  36                                            BCM2835_AUX_CLOCK_COUNT),
  37                                GFP_KERNEL);
  38         if (!onecell)
  39                 return -ENOMEM;
  40         onecell->num = BCM2835_AUX_CLOCK_COUNT;
  41
  42         gate = reg + BCM2835_AUXENB;
  43         onecell->hws[BCM2835_AUX_CLOCK_UART] =
  44                 clk_hw_register_gate(dev, "aux_uart", parent, 0, gate, 0, 0, NULL);
  45
  46         onecell->hws[BCM2835_AUX_CLOCK_SPI1] =
  47                 clk_hw_register_gate(dev, "aux_spi1", parent, 0, gate, 1, 0, NULL);
  48
  49         onecell->hws[BCM2835_AUX_CLOCK_SPI2] =
  50                 clk_hw_register_gate(dev, "aux_spi2", parent, 0, gate, 2, 0, NULL);
  51
  52         return of_clk_add_hw_provider(pdev->dev.of_node, of_clk_hw_onecell_get,
  53                                       onecell);
  54 }
  55
  56 static const struct of_device_id bcm2835_aux_clk_of_match[] = {
  57         { .compatible = "brcm,bcm2835-aux", },
  58         {},
  59 };
  60 MODULE_DEVICE_TABLE(of, bcm2835_aux_clk_of_match);
  61
  62 static struct platform_driver bcm2835_aux_clk_driver = {
  63         .driver = {
  64                 .name = "bcm2835-aux-clk",
  65                 .of_match_table = bcm2835_aux_clk_of_match,
  66         },
  67         .probe          = bcm2835_aux_clk_probe,
  68 };
  69 builtin_platform_driver(bcm2835_aux_clk_driver);
  70
  71 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
  72 MODULE_DESCRIPTION("BCM2835 auxiliary peripheral clock driver");
  73 MODULE_LICENSE("GPL");