1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org> 4 */ 5 6 #include <linux/device.h> 7 #include <linux/module.h> 8 #include <linux/mod_devicetable.h> 9 #include <linux/io.h> 10 #include <linux/nvmem-provider.h> 11 #include <linux/platform_device.h> 12 13 struct qfprom_priv { 14 void __iomem *base; 15 }; 16 17 static int qfprom_reg_read(void *context, 18 unsigned int reg, void *_val, size_t bytes) 19 { 20 struct qfprom_priv *priv = context; 21 u8 *val = _val; 22 int i = 0, words = bytes; 23 24 while (words--) 25 *val++ = readb(priv->base + reg + i++); 26 27 return 0; 28 } 29 30 static int qfprom_reg_write(void *context, 31 unsigned int reg, void *_val, size_t bytes) 32 { 33 struct qfprom_priv *priv = context; 34 u8 *val = _val; 35 int i = 0, words = bytes; 36 37 while (words--) 38 writeb(*val++, priv->base + reg + i++); 39 40 return 0; 41 } 42 43 static struct nvmem_config econfig = { 44 .name = "qfprom", 45 .stride = 1, 46 .word_size = 1, 47 .reg_read = qfprom_reg_read, 48 .reg_write = qfprom_reg_write, 49 }; 50 51 static int qfprom_probe(struct platform_device *pdev) 52 { 53 struct device *dev = &pdev->dev; 54 struct resource *res; 55 struct nvmem_device *nvmem; 56 struct qfprom_priv *priv; 57 58 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 59 if (!priv) 60 return -ENOMEM; 61 62 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 63 priv->base = devm_ioremap_resource(dev, res); 64 if (IS_ERR(priv->base)) 65 return PTR_ERR(priv->base); 66 67 econfig.size = resource_size(res); 68 econfig.dev = dev; 69 econfig.priv = priv; 70 71 nvmem = devm_nvmem_register(dev, &econfig); 72 73 return PTR_ERR_OR_ZERO(nvmem); 74 } 75 76 static const struct of_device_id qfprom_of_match[] = { 77 { .compatible = "qcom,qfprom",}, 78 {/* sentinel */}, 79 }; 80 MODULE_DEVICE_TABLE(of, qfprom_of_match); 81 82 static struct platform_driver qfprom_driver = { 83 .probe = qfprom_probe, 84 .driver = { 85 .name = "qcom,qfprom", 86 .of_match_table = qfprom_of_match, 87 }, 88 }; 89 module_platform_driver(qfprom_driver); 90 MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>"); 91 MODULE_DESCRIPTION("Qualcomm QFPROM driver"); 92 MODULE_LICENSE("GPL v2"); 93