diff options
Diffstat (limited to 'drivers/ufs/host/ti-j721e-ufs.c')
-rw-r--r-- | drivers/ufs/host/ti-j721e-ufs.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/ufs/host/ti-j721e-ufs.c b/drivers/ufs/host/ti-j721e-ufs.c new file mode 100644 index 000000000000..122d650d0810 --- /dev/null +++ b/drivers/ufs/host/ti-j721e-ufs.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ +// + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#define TI_UFS_SS_CTRL 0x4 +#define TI_UFS_SS_RST_N_PCS BIT(0) +#define TI_UFS_SS_CLK_26MHZ BIT(4) + +static int ti_j721e_ufs_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + unsigned long clk_rate; + void __iomem *regbase; + struct clk *clk; + u32 reg = 0; + int ret; + + regbase = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(regbase)) + return PTR_ERR(regbase); + + pm_runtime_enable(dev); + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + goto disable_pm; + + /* Select MPHY refclk frequency */ + clk = devm_clk_get(dev, NULL); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + dev_err(dev, "Cannot claim MPHY clock.\n"); + goto clk_err; + } + clk_rate = clk_get_rate(clk); + if (clk_rate == 26000000) + reg |= TI_UFS_SS_CLK_26MHZ; + devm_clk_put(dev, clk); + + /* Take UFS slave device out of reset */ + reg |= TI_UFS_SS_RST_N_PCS; + writel(reg, regbase + TI_UFS_SS_CTRL); + + ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, + dev); + if (ret) { + dev_err(dev, "failed to populate child nodes %d\n", ret); + goto clk_err; + } + + return ret; + +clk_err: + pm_runtime_put_sync(dev); +disable_pm: + pm_runtime_disable(dev); + return ret; +} + +static int ti_j721e_ufs_remove(struct platform_device *pdev) +{ + of_platform_depopulate(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct of_device_id ti_j721e_ufs_of_match[] = { + { + .compatible = "ti,j721e-ufs", + }, + { }, +}; + +static struct platform_driver ti_j721e_ufs_driver = { + .probe = ti_j721e_ufs_probe, + .remove = ti_j721e_ufs_remove, + .driver = { + .name = "ti-j721e-ufs", + .of_match_table = ti_j721e_ufs_of_match, + }, +}; +module_platform_driver(ti_j721e_ufs_driver); + +MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>"); +MODULE_DESCRIPTION("TI UFS host controller glue driver"); +MODULE_LICENSE("GPL v2"); |