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/module.h> 24 #include <linux/slab.h> 25 #include <linux/platform_device.h> 26 #include <linux/mfd/twl6040.h> 27 #include <linux/clk-provider.h> 28 29 struct twl6040_pdmclk { 30 struct twl6040 *twl6040; 31 struct device *dev; 32 struct clk_hw pdmclk_hw; 33 int enabled; 34 }; 35 36 static int twl6040_pdmclk_is_prepared(struct clk_hw *hw) 37 { 38 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, 39 pdmclk_hw); 40 41 return pdmclk->enabled; 42 } 43 44 static int twl6040_pdmclk_prepare(struct clk_hw *hw) 45 { 46 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, 47 pdmclk_hw); 48 int ret; 49 50 ret = twl6040_power(pdmclk->twl6040, 1); 51 if (!ret) 52 pdmclk->enabled = 1; 53 54 return ret; 55 } 56 57 static void twl6040_pdmclk_unprepare(struct clk_hw *hw) 58 { 59 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, 60 pdmclk_hw); 61 int ret; 62 63 ret = twl6040_power(pdmclk->twl6040, 0); 64 if (!ret) 65 pdmclk->enabled = 0; 66 67 } 68 69 static unsigned long twl6040_pdmclk_recalc_rate(struct clk_hw *hw, 70 unsigned long parent_rate) 71 { 72 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, 73 pdmclk_hw); 74 75 return twl6040_get_sysclk(pdmclk->twl6040); 76 } 77 78 static const struct clk_ops twl6040_pdmclk_ops = { 79 .is_prepared = twl6040_pdmclk_is_prepared, 80 .prepare = twl6040_pdmclk_prepare, 81 .unprepare = twl6040_pdmclk_unprepare, 82 .recalc_rate = twl6040_pdmclk_recalc_rate, 83 }; 84 85 static struct clk_init_data twl6040_pdmclk_init = { 86 .name = "pdmclk", 87 .ops = &twl6040_pdmclk_ops, 88 .flags = CLK_GET_RATE_NOCACHE, 89 }; 90 91 static int twl6040_pdmclk_probe(struct platform_device *pdev) 92 { 93 struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent); 94 struct twl6040_pdmclk *clkdata; 95 int ret; 96 97 clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL); 98 if (!clkdata) 99 return -ENOMEM; 100 101 clkdata->dev = &pdev->dev; 102 clkdata->twl6040 = twl6040; 103 104 clkdata->pdmclk_hw.init = &twl6040_pdmclk_init; 105 ret = devm_clk_hw_register(&pdev->dev, &clkdata->pdmclk_hw); 106 if (ret) 107 return ret; 108 109 platform_set_drvdata(pdev, clkdata); 110 111 return of_clk_add_hw_provider(pdev->dev.parent->of_node, 112 of_clk_hw_simple_get, 113 &clkdata->pdmclk_hw); 114 } 115 116 static struct platform_driver twl6040_pdmclk_driver = { 117 .driver = { 118 .name = "twl6040-pdmclk", 119 }, 120 .probe = twl6040_pdmclk_probe, 121 }; 122 123 module_platform_driver(twl6040_pdmclk_driver); 124 125 MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock"); 126 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); 127 MODULE_ALIAS("platform:twl6040-pdmclk"); 128 MODULE_LICENSE("GPL"); 129