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/io.h> 17 #include <linux/nvmem-provider.h> 18 #include <linux/platform_device.h> 19 20 struct qfprom_priv { 21 void __iomem *base; 22 }; 23 24 static int qfprom_reg_read(void *context, 25 unsigned int reg, void *_val, size_t bytes) 26 { 27 struct qfprom_priv *priv = context; 28 u8 *val = _val; 29 int i = 0, words = bytes; 30 31 while (words--) 32 *val++ = readb(priv->base + reg + i++); 33 34 return 0; 35 } 36 37 static int qfprom_reg_write(void *context, 38 unsigned int reg, void *_val, size_t bytes) 39 { 40 struct qfprom_priv *priv = context; 41 u8 *val = _val; 42 int i = 0, words = bytes; 43 44 while (words--) 45 writeb(*val++, priv->base + reg + i++); 46 47 return 0; 48 } 49 50 static struct nvmem_config econfig = { 51 .name = "qfprom", 52 .stride = 1, 53 .word_size = 1, 54 .reg_read = qfprom_reg_read, 55 .reg_write = qfprom_reg_write, 56 }; 57 58 static int qfprom_probe(struct platform_device *pdev) 59 { 60 struct device *dev = &pdev->dev; 61 struct resource *res; 62 struct nvmem_device *nvmem; 63 struct qfprom_priv *priv; 64 65 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 66 if (!priv) 67 return -ENOMEM; 68 69 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 70 priv->base = devm_ioremap_resource(dev, res); 71 if (IS_ERR(priv->base)) 72 return PTR_ERR(priv->base); 73 74 econfig.size = resource_size(res); 75 econfig.dev = dev; 76 econfig.priv = priv; 77 78 nvmem = devm_nvmem_register(dev, &econfig); 79 80 return PTR_ERR_OR_ZERO(nvmem); 81 } 82 83 static const struct of_device_id qfprom_of_match[] = { 84 { .compatible = "qcom,qfprom",}, 85 {/* sentinel */}, 86 }; 87 MODULE_DEVICE_TABLE(of, qfprom_of_match); 88 89 static struct platform_driver qfprom_driver = { 90 .probe = qfprom_probe, 91 .driver = { 92 .name = "qcom,qfprom", 93 .of_match_table = qfprom_of_match, 94 }, 95 }; 96 module_platform_driver(qfprom_driver); 97 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>"); 98 MODULE_DESCRIPTION("Qualcomm QFPROM driver"); 99 MODULE_LICENSE("GPL v2"); 100