diff options
Diffstat (limited to 'drivers/spi/dw_spi_mmio.c')
-rw-r--r-- | drivers/spi/dw_spi_mmio.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/spi/dw_spi_mmio.c b/drivers/spi/dw_spi_mmio.c new file mode 100644 index 0000000..e35b45a --- /dev/null +++ b/drivers/spi/dw_spi_mmio.c @@ -0,0 +1,147 @@ +/* + * dw_spi_mmio.c - Memory-mapped interface driver for DW SPI Core + * + * Copyright (c) 2010, Octasic semiconductor. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/spi/dw_spi.h> +#include <linux/spi/spi.h> + +#define DRIVER_NAME "dw_spi_mmio" + +struct dw_spi_mmio { + struct dw_spi dws; + struct clk *clk; +}; + +static int __devinit dw_spi_mmio_probe(struct platform_device *pdev) +{ + struct dw_spi_mmio *dwsmmio; + struct dw_spi *dws; + struct resource *mem, *ioarea; + int ret; + + dwsmmio = kzalloc(sizeof(struct dw_spi_mmio), GFP_KERNEL); + if (!dwsmmio) { + ret = -ENOMEM; + goto err_end; + } + + dws = &dwsmmio->dws; + + /* Get basic io resource and map it */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) { + dev_err(&pdev->dev, "no mem resource?\n"); + ret = -EINVAL; + goto err_kfree; + } + + ioarea = request_mem_region(mem->start, resource_size(mem), + pdev->name); + if (!ioarea) { + dev_err(&pdev->dev, "SPI region already claimed\n"); + ret = -EBUSY; + goto err_kfree; + } + + dws->regs = ioremap_nocache(mem->start, resource_size(mem)); + if (!dws->regs) { + dev_err(&pdev->dev, "SPI region already mapped\n"); + ret = -ENOMEM; + goto err_release_reg; + } + + dws->irq = platform_get_irq(pdev, 0); + if (dws->irq < 0) { + dev_err(&pdev->dev, "no irq resource?\n"); + ret = dws->irq; /* -ENXIO */ + goto err_unmap; + } + + dwsmmio->clk = clk_get(&pdev->dev, NULL); + if (!dwsmmio->clk) { + ret = -ENODEV; + goto err_irq; + } + clk_enable(dwsmmio->clk); + + dws->parent_dev = &pdev->dev; + dws->bus_num = 0; + dws->num_cs = 4; + dws->max_freq = clk_get_rate(dwsmmio->clk); + + ret = dw_spi_add_host(dws); + if (ret) + goto err_clk; + + platform_set_drvdata(pdev, dwsmmio); + return 0; + +err_clk: + clk_disable(dwsmmio->clk); + clk_put(dwsmmio->clk); + dwsmmio->clk = NULL; +err_irq: + free_irq(dws->irq, dws); +err_unmap: + iounmap(dws->regs); +err_release_reg: + release_mem_region(mem->start, resource_size(mem)); +err_kfree: + kfree(dwsmmio); +err_end: + return ret; +} + +static int __devexit dw_spi_mmio_remove(struct platform_device *pdev) +{ + struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev); + struct resource *mem; + + platform_set_drvdata(pdev, NULL); + + clk_disable(dwsmmio->clk); + clk_put(dwsmmio->clk); + dwsmmio->clk = NULL; + + free_irq(dwsmmio->dws.irq, &dwsmmio->dws); + dw_spi_remove_host(&dwsmmio->dws); + iounmap(dwsmmio->dws.regs); + kfree(dwsmmio); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mem->start, resource_size(mem)); + return 0; +} + +static struct platform_driver dw_spi_mmio_driver = { + .remove = __devexit_p(dw_spi_mmio_remove), + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init dw_spi_mmio_init(void) +{ + return platform_driver_probe(&dw_spi_mmio_driver, dw_spi_mmio_probe); +} +module_init(dw_spi_mmio_init); + +static void __exit dw_spi_mmio_exit(void) +{ + platform_driver_unregister(&dw_spi_mmio_driver); +} +module_exit(dw_spi_mmio_exit); + +MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>"); +MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core"); +MODULE_LICENSE("GPL v2"); |