1 /* 2 * TWL6040 clock module driver for OMAP4 McPDM functional clock 3 * 4 * Copyright (C) 2012 Texas Instruments Inc. 5 * Peter Ujfalusi <peter.ujfalusi@ti.com> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * version 2 as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, but 12 * WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 19 * 02110-1301 USA 20 * 21 */ 22 23 #include <linux/clk.h> 24 #include <linux/module.h> 25 #include <linux/slab.h> 26 #include <linux/platform_device.h> 27 #include <linux/mfd/twl6040.h> 28 #include <linux/clk-provider.h> 29 30 struct twl6040_clk { 31 struct twl6040 *twl6040; 32 struct device *dev; 33 struct clk_hw mcpdm_fclk; 34 struct clk *clk; 35 int enabled; 36 }; 37 38 static int twl6040_bitclk_is_enabled(struct clk_hw *hw) 39 { 40 struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk, 41 mcpdm_fclk); 42 return twl6040_clk->enabled; 43 } 44 45 static int twl6040_bitclk_prepare(struct clk_hw *hw) 46 { 47 struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk, 48 mcpdm_fclk); 49 int ret; 50 51 ret = twl6040_power(twl6040_clk->twl6040, 1); 52 if (!ret) 53 twl6040_clk->enabled = 1; 54 55 return ret; 56 } 57 58 static void twl6040_bitclk_unprepare(struct clk_hw *hw) 59 { 60 struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk, 61 mcpdm_fclk); 62 int ret; 63 64 ret = twl6040_power(twl6040_clk->twl6040, 0); 65 if (!ret) 66 twl6040_clk->enabled = 0; 67 } 68 69 static const struct clk_ops twl6040_mcpdm_ops = { 70 .is_enabled = twl6040_bitclk_is_enabled, 71 .prepare = twl6040_bitclk_prepare, 72 .unprepare = twl6040_bitclk_unprepare, 73 }; 74 75 static struct clk_init_data wm831x_clkout_init = { 76 .name = "mcpdm_fclk", 77 .ops = &twl6040_mcpdm_ops, 78 .flags = CLK_IS_ROOT, 79 }; 80 81 static int twl6040_clk_probe(struct platform_device *pdev) 82 { 83 struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent); 84 struct twl6040_clk *clkdata; 85 86 clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL); 87 if (!clkdata) 88 return -ENOMEM; 89 90 clkdata->dev = &pdev->dev; 91 clkdata->twl6040 = twl6040; 92 93 clkdata->mcpdm_fclk.init = &wm831x_clkout_init; 94 clkdata->clk = clk_register(&pdev->dev, &clkdata->mcpdm_fclk); 95 if (IS_ERR(clkdata->clk)) 96 return PTR_ERR(clkdata->clk); 97 98 platform_set_drvdata(pdev, clkdata); 99 100 return 0; 101 } 102 103 static int twl6040_clk_remove(struct platform_device *pdev) 104 { 105 struct twl6040_clk *clkdata = platform_get_drvdata(pdev); 106 107 clk_unregister(clkdata->clk); 108 109 return 0; 110 } 111 112 static struct platform_driver twl6040_clk_driver = { 113 .driver = { 114 .name = "twl6040-clk", 115 }, 116 .probe = twl6040_clk_probe, 117 .remove = twl6040_clk_remove, 118 }; 119 120 module_platform_driver(twl6040_clk_driver); 121 122 MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock"); 123 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); 124 MODULE_ALIAS("platform:twl6040-clk"); 125 MODULE_LICENSE("GPL"); 126