1 /* 2 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 and 6 * only version 2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 */ 13 14 #include <linux/device.h> 15 #include <linux/module.h> 16 #include <linux/mod_devicetable.h> 17 #include <linux/io.h> 18 #include <linux/nvmem-provider.h> 19 #include <linux/platform_device.h> 20 21 struct qfprom_priv { 22 void __iomem *base; 23 }; 24 25 static int qfprom_reg_read(void *context, 26 unsigned int reg, void *_val, size_t bytes) 27 { 28 struct qfprom_priv *priv = context; 29 u8 *val = _val; 30 int i = 0, words = bytes; 31 32 while (words--) 33 *val++ = readb(priv->base + reg + i++); 34 35 return 0; 36 } 37 38 static int qfprom_reg_write(void *context, 39 unsigned int reg, void *_val, size_t bytes) 40 { 41 struct qfprom_priv *priv = context; 42 u8 *val = _val; 43 int i = 0, words = bytes; 44 45 while (words--) 46 writeb(*val++, priv->base + reg + i++); 47 48 return 0; 49 } 50 51 static struct nvmem_config econfig = { 52 .name = "qfprom", 53 .stride = 1, 54 .word_size = 1, 55 .reg_read = qfprom_reg_read, 56 .reg_write = qfprom_reg_write, 57 }; 58 59 static int qfprom_probe(struct platform_device *pdev) 60 { 61 struct device *dev = &pdev->dev; 62 struct resource *res; 63 struct nvmem_device *nvmem; 64 struct qfprom_priv *priv; 65 66 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 67 if (!priv) 68 return -ENOMEM; 69 70 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 71 priv->base = devm_ioremap_resource(dev, res); 72 if (IS_ERR(priv->base)) 73 return PTR_ERR(priv->base); 74 75 econfig.size = resource_size(res); 76 econfig.dev = dev; 77 econfig.priv = priv; 78 79 nvmem = devm_nvmem_register(dev, &econfig); 80 81 return PTR_ERR_OR_ZERO(nvmem); 82 } 83 84 static const struct of_device_id qfprom_of_match[] = { 85 { .compatible = "qcom,qfprom",}, 86 {/* sentinel */}, 87 }; 88 MODULE_DEVICE_TABLE(of, qfprom_of_match); 89 90 static struct platform_driver qfprom_driver = { 91 .probe = qfprom_probe, 92 .driver = { 93 .name = "qcom,qfprom", 94 .of_match_table = qfprom_of_match, 95 }, 96 }; 97 module_platform_driver(qfprom_driver); 98 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>"); 99 MODULE_DESCRIPTION("Qualcomm QFPROM driver"); 100 MODULE_LICENSE("GPL v2"); 101