From 5d144e36b7c51612922fa05d37ff3a869261cc82 Mon Sep 17 00:00:00 2001 From: Andy Gross Date: Thu, 24 Apr 2014 11:31:21 -0500 Subject: [PATCH] soc: qcom: Add GSBI driver The GSBI (General Serial Bus Interface) driver controls the overarching configuration of the shared serial bus infrastructure on APQ8064, IPQ8064, and earlier QCOM processors. The GSBI supports UART, I2C, SPI, and UIM functionality in various combinations. Signed-off-by: Andy Gross Signed-off-by: Kumar Gala --- drivers/soc/Kconfig | 2 + drivers/soc/Makefile | 5 +++ drivers/soc/qcom/Kconfig | 11 +++++ drivers/soc/qcom/Makefile | 1 + drivers/soc/qcom/qcom_gsbi.c | 84 ++++++++++++++++++++++++++++++++++++ 5 files changed, 103 insertions(+) create mode 100644 drivers/soc/Makefile create mode 100644 drivers/soc/qcom/Kconfig create mode 100644 drivers/soc/qcom/Makefile create mode 100644 drivers/soc/qcom/qcom_gsbi.c diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig index 339baa87336f..c8543855aa82 100644 --- a/drivers/soc/Kconfig +++ b/drivers/soc/Kconfig @@ -1,3 +1,5 @@ menu "SOC (System On Chip) specific Drivers" +source "drivers/soc/qcom/Kconfig" + endmenu diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile new file mode 100644 index 000000000000..0f7c44793b29 --- /dev/null +++ b/drivers/soc/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for the Linux Kernel SOC specific device drivers. +# + +obj-$(CONFIG_ARCH_QCOM) += qcom/ diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig new file mode 100644 index 000000000000..7bd2c94f54a4 --- /dev/null +++ b/drivers/soc/qcom/Kconfig @@ -0,0 +1,11 @@ +# +# QCOM Soc drivers +# +config QCOM_GSBI + tristate "QCOM General Serial Bus Interface" + depends on ARCH_QCOM + help + Say y here to enable GSBI support. The GSBI provides control + functions for connecting the underlying serial UART, SPI, and I2C + devices to the output pins. + diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile new file mode 100644 index 000000000000..438901257ac1 --- /dev/null +++ b/drivers/soc/qcom/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_QCOM_GSBI) += qcom_gsbi.o diff --git a/drivers/soc/qcom/qcom_gsbi.c b/drivers/soc/qcom/qcom_gsbi.c new file mode 100644 index 000000000000..061dd0632dbd --- /dev/null +++ b/drivers/soc/qcom/qcom_gsbi.c @@ -0,0 +1,84 @@ +/* + * Copyright (c) 2014, The Linux foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License rev 2 and + * only rev 2 as published by the free Software foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or fITNESS fOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define GSBI_CTRL_REG 0x0000 +#define GSBI_PROTOCOL_SHIFT 4 + +static int gsbi_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct resource *res; + void __iomem *base; + struct clk *hclk; + u32 mode, crci = 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + if (of_property_read_u32(node, "qcom,mode", &mode)) { + dev_err(&pdev->dev, "missing mode configuration\n"); + return -EINVAL; + } + + /* not required, so default to 0 if not present */ + of_property_read_u32(node, "qcom,crci", &crci); + + dev_info(&pdev->dev, "GSBI port protocol: %d crci: %d\n", mode, crci); + + hclk = devm_clk_get(&pdev->dev, "iface"); + if (IS_ERR(hclk)) + return PTR_ERR(hclk); + + clk_prepare_enable(hclk); + + writel_relaxed((mode << GSBI_PROTOCOL_SHIFT) | crci, + base + GSBI_CTRL_REG); + + /* make sure the gsbi control write is not reordered */ + wmb(); + + clk_disable_unprepare(hclk); + + return of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); +} + +static const struct of_device_id gsbi_dt_match[] = { + { .compatible = "qcom,gsbi-v1.0.0", }, +}; + +MODULE_DEVICE_TABLE(of, gsbi_dt_match); + +static struct platform_driver gsbi_driver = { + .driver = { + .name = "gsbi", + .owner = THIS_MODULE, + .of_match_table = gsbi_dt_match, + }, + .probe = gsbi_probe, +}; + +module_platform_driver(gsbi_driver); + +MODULE_AUTHOR("Andy Gross "); +MODULE_DESCRIPTION("QCOM GSBI driver"); +MODULE_LICENSE("GPL v2"); -- 2.34.1