cregit-Linux how code gets into the kernel

Release 4.7 drivers/tty/serial/8250/8250_bcm2835aux.c

/*
 * Serial port driver for BCM2835AUX UART
 *
 * Copyright (C) 2016 Martin Sperl <kernel@martin.sperl.org>
 *
 * Based on 8250_lpc18xx.c:
 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>

#include "8250.h"


struct bcm2835aux_data {
	
struct uart_8250_port uart;
	
struct clk *clk;
	
int line;
};


static int bcm2835aux_serial_probe(struct platform_device *pdev) { struct bcm2835aux_data *data; struct resource *res; int ret; /* allocate the custom structure */ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; /* initialize data */ spin_lock_init(&data->uart.port.lock); data->uart.capabilities = UART_CAP_FIFO; data->uart.port.dev = &pdev->dev; data->uart.port.regshift = 2; data->uart.port.type = PORT_16550; data->uart.port.iotype = UPIO_MEM; data->uart.port.fifosize = 8; data->uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_SKIP_TEST; /* get the clock - this also enables the HW */ data->clk = devm_clk_get(&pdev->dev, NULL); ret = PTR_ERR_OR_ZERO(data->clk); if (ret) { dev_err(&pdev->dev, "could not get clk: %d\n", ret); return ret; } /* get the interrupt */ ret = platform_get_irq(pdev, 0); if (ret < 0) { dev_err(&pdev->dev, "irq not found - %i", ret); return ret; } data->uart.port.irq = ret; /* map the main registers */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "memory resource not found"); return -EINVAL; } data->uart.port.membase = devm_ioremap_resource(&pdev->dev, res); ret = PTR_ERR_OR_ZERO(data->uart.port.membase); if (ret) return ret; /* Check for a fixed line number */ ret = of_alias_get_id(pdev->dev.of_node, "serial"); if (ret >= 0) data->uart.port.line = ret; /* enable the clock as a last step */ ret = clk_prepare_enable(data->clk); if (ret) { dev_err(&pdev->dev, "unable to enable uart clock - %d\n", ret); return ret; } /* the HW-clock divider for bcm2835aux is 8, * but 8250 expects a divider of 16, * so we have to multiply the actual clock by 2 * to get identical baudrates. */ data->uart.port.uartclk = clk_get_rate(data->clk) * 2; /* register the port */ ret = serial8250_register_8250_port(&data->uart); if (ret < 0) { dev_err(&pdev->dev, "unable to register 8250 port - %d\n", ret); goto dis_clk; } data->line = ret; platform_set_drvdata(pdev, data); return 0; dis_clk: clk_disable_unprepare(data->clk); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
martin sperlmartin sperl442100.00%2100.00%
Total442100.00%2100.00%


static int bcm2835aux_serial_remove(struct platform_device *pdev) { struct bcm2835aux_data *data = platform_get_drvdata(pdev); serial8250_unregister_port(data->uart.port.line); clk_disable_unprepare(data->clk); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
martin sperlmartin sperl42100.00%1100.00%
Total42100.00%1100.00%

static const struct of_device_id bcm2835aux_serial_match[] = { { .compatible = "brcm,bcm2835-aux-uart" }, { }, }; MODULE_DEVICE_TABLE(of, bcm2835aux_serial_match); static struct platform_driver bcm2835aux_serial_driver = { .driver = { .name = "bcm2835-aux-uart", .of_match_table = bcm2835aux_serial_match, }, .probe = bcm2835aux_serial_probe, .remove = bcm2835aux_serial_remove, }; module_platform_driver(bcm2835aux_serial_driver); MODULE_DESCRIPTION("BCM2835 auxiliar UART driver"); MODULE_AUTHOR("Martin Sperl <kernel@martin.sperl.org>"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
martin sperlmartin sperl597100.00%2100.00%
Total597100.00%2100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}