1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * Freescale MXS On-Chip OTP driver
15 #include <linux/nvmem-provider.h>
37 static int mxs_ocotp_wait(struct mxs_ocotp *otp)  in mxs_ocotp_wait()  argument
42 	while (timeout--) {  in mxs_ocotp_wait()
43 		status = readl(otp->base);  in mxs_ocotp_wait()
52 		return -EBUSY;  in mxs_ocotp_wait()
54 		return -EIO;  in mxs_ocotp_wait()
62 	struct mxs_ocotp *otp = context;  in mxs_ocotp_read()  local
66 	ret = clk_enable(otp->clk);  in mxs_ocotp_read()
70 	writel(BM_OCOTP_CTRL_ERROR, otp->base + STMP_OFFSET_REG_CLR);  in mxs_ocotp_read()
72 	ret = mxs_ocotp_wait(otp);  in mxs_ocotp_read()
77 	writel(BM_OCOTP_CTRL_RD_BANK_OPEN, otp->base + STMP_OFFSET_REG_SET);  in mxs_ocotp_read()
80 	udelay(1);  in mxs_ocotp_read()
82 	ret = mxs_ocotp_wait(otp);  in mxs_ocotp_read()
88 			/* fill up non-data register */  in mxs_ocotp_read()
91 			*buf++ = readl(otp->base + offset);  in mxs_ocotp_read()
94 		bytes -= 4;  in mxs_ocotp_read()
100 	writel(BM_OCOTP_CTRL_RD_BANK_OPEN, otp->base + STMP_OFFSET_REG_CLR);  in mxs_ocotp_read()
103 	clk_disable(otp->clk);  in mxs_ocotp_read()
109 	.name = "mxs-ocotp",
128 	{ .compatible = "fsl,imx23-ocotp", .data = &imx23_data },
129 	{ .compatible = "fsl,imx28-ocotp", .data = &imx28_data },
141 	struct device *dev = &pdev->dev;  in mxs_ocotp_probe()
143 	struct mxs_ocotp *otp;  in mxs_ocotp_probe()  local
148 		return -EINVAL;  in mxs_ocotp_probe()
150 	otp = devm_kzalloc(dev, sizeof(*otp), GFP_KERNEL);  in mxs_ocotp_probe()
151 	if (!otp)  in mxs_ocotp_probe()
152 		return -ENOMEM;  in mxs_ocotp_probe()
154 	otp->base = devm_platform_ioremap_resource(pdev, 0);  in mxs_ocotp_probe()
155 	if (IS_ERR(otp->base))  in mxs_ocotp_probe()
156 		return PTR_ERR(otp->base);  in mxs_ocotp_probe()
158 	otp->clk = devm_clk_get(&pdev->dev, NULL);  in mxs_ocotp_probe()
159 	if (IS_ERR(otp->clk))  in mxs_ocotp_probe()
160 		return PTR_ERR(otp->clk);  in mxs_ocotp_probe()
162 	ret = clk_prepare(otp->clk);  in mxs_ocotp_probe()
168 	ret = devm_add_action_or_reset(&pdev->dev, mxs_ocotp_action, otp->clk);  in mxs_ocotp_probe()
172 	ocotp_config.size = data->size;  in mxs_ocotp_probe()
173 	ocotp_config.priv = otp;  in mxs_ocotp_probe()
175 	otp->nvmem = devm_nvmem_register(dev, &ocotp_config);  in mxs_ocotp_probe()
176 	if (IS_ERR(otp->nvmem))  in mxs_ocotp_probe()
177 		return PTR_ERR(otp->nvmem);  in mxs_ocotp_probe()
179 	platform_set_drvdata(pdev, otp);  in mxs_ocotp_probe()
187 		.name = "mxs-ocotp",