diff options
author | Juergen Fitschen <me@jue.yt> | 2019-02-22 12:25:21 +0300 |
---|---|---|
committer | Wolfram Sang <wsa@the-dreams.de> | 2019-03-25 00:41:51 +0300 |
commit | ad7d142f8951ce00e0366ba54bfaf8ab086eb4b9 (patch) | |
tree | 94aac003feaaefde4272b3dfefb1f7e7120f1c83 | |
parent | 07345ab220d80ac7edf4b6bfa4b43800dfbd2c97 (diff) | |
download | linux-ad7d142f8951ce00e0366ba54bfaf8ab086eb4b9.tar.xz |
i2c: at91: split driver into core and master file
The single file i2c-at91.c has been split into core code (i2c-at91-core.c)
and master mode specific code (i2c-at91-master.c). This should enhance
maintainability and reduce ifdeffery for slave mode related code.
The code itself hasn't been touched. Shared functions only had to be made
non-static. Furthermore, includes have been cleaned up.
Signed-off-by: Juergen Fitschen <me@jue.yt>
[ludovic.desroches@microchip.com: fix checkpatch errors and use SPDX]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
-rw-r--r-- | MAINTAINERS | 3 | ||||
-rw-r--r-- | drivers/i2c/busses/Makefile | 1 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-at91-core.c | 369 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-at91-master.c (renamed from drivers/i2c/busses/i2c-at91.c) | 473 | ||||
-rw-r--r-- | drivers/i2c/busses/i2c-at91.h | 147 |
5 files changed, 524 insertions, 469 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index e17ebf70b548..a766c8f13b22 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10102,7 +10102,8 @@ MICROCHIP I2C DRIVER M: Ludovic Desroches <ludovic.desroches@microchip.com> L: linux-i2c@vger.kernel.org S: Supported -F: drivers/i2c/busses/i2c-at91.c +F: drivers/i2c/busses/i2c-at91.h +F: drivers/i2c/busses/i2c-at91-*.c MICROCHIP ISC DRIVER M: Eugen Hristev <eugen.hristev@microchip.com> diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 5f0cb6915969..ea75a777940e 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o obj-$(CONFIG_I2C_ALTERA) += i2c-altera.o obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o obj-$(CONFIG_I2C_AT91) += i2c-at91.o +i2c-at91-objs := i2c-at91-core.o i2c-at91-master.o obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o obj-$(CONFIG_I2C_AXXIA) += i2c-axxia.o obj-$(CONFIG_I2C_BCM2835) += i2c-bcm2835.o diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c new file mode 100644 index 000000000000..6cb22341fa81 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91-core.c @@ -0,0 +1,369 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2011 Weinmann Medical GmbH + * Author: Nikolaus Voss <n.voss@weinmann.de> + * + * Evolved from original work by: + * Copyright (C) 2004 Rick Bronson + * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com> + * + * Borrowed heavily from original work by: + * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> + +#include "i2c-at91.h" + +unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg) +{ + return readl_relaxed(dev->base + reg); +} + +void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val) +{ + writel_relaxed(val, dev->base + reg); +} + +void at91_disable_twi_interrupts(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK); +} + +void at91_twi_irq_save(struct at91_twi_dev *dev) +{ + dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK; + at91_disable_twi_interrupts(dev); +} + +void at91_twi_irq_restore(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_IER, dev->imr); +} + +void at91_init_twi_bus(struct at91_twi_dev *dev) +{ + at91_disable_twi_interrupts(dev); + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST); + + at91_init_twi_bus_master(dev); +} + +static struct at91_twi_pdata at91rm9200_config = { + .clk_max_div = 5, + .clk_offset = 3, + .has_unre_flag = true, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static struct at91_twi_pdata at91sam9261_config = { + .clk_max_div = 5, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static struct at91_twi_pdata at91sam9260_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static struct at91_twi_pdata at91sam9g20_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static struct at91_twi_pdata at91sam9g10_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static const struct platform_device_id at91_twi_devtypes[] = { + { + .name = "i2c-at91rm9200", + .driver_data = (unsigned long) &at91rm9200_config, + }, { + .name = "i2c-at91sam9261", + .driver_data = (unsigned long) &at91sam9261_config, + }, { + .name = "i2c-at91sam9260", + .driver_data = (unsigned long) &at91sam9260_config, + }, { + .name = "i2c-at91sam9g20", + .driver_data = (unsigned long) &at91sam9g20_config, + }, { + .name = "i2c-at91sam9g10", + .driver_data = (unsigned long) &at91sam9g10_config, + }, { + /* sentinel */ + } +}; + +#if defined(CONFIG_OF) +static struct at91_twi_pdata at91sam9x5_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = false, +}; + +static struct at91_twi_pdata sama5d4_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = false, + .has_alt_cmd = false, + .has_hold_field = true, +}; + +static struct at91_twi_pdata sama5d2_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_unre_flag = true, + .has_alt_cmd = true, + .has_hold_field = true, +}; + +static const struct of_device_id atmel_twi_dt_ids[] = { + { + .compatible = "atmel,at91rm9200-i2c", + .data = &at91rm9200_config, + }, { + .compatible = "atmel,at91sam9260-i2c", + .data = &at91sam9260_config, + }, { + .compatible = "atmel,at91sam9261-i2c", + .data = &at91sam9261_config, + }, { + .compatible = "atmel,at91sam9g20-i2c", + .data = &at91sam9g20_config, + }, { + .compatible = "atmel,at91sam9g10-i2c", + .data = &at91sam9g10_config, + }, { + .compatible = "atmel,at91sam9x5-i2c", + .data = &at91sam9x5_config, + }, { + .compatible = "atmel,sama5d4-i2c", + .data = &sama5d4_config, + }, { + .compatible = "atmel,sama5d2-i2c", + .data = &sama5d2_config, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids); +#endif + +static struct at91_twi_pdata *at91_twi_get_driver_data( + struct platform_device *pdev) +{ + if (pdev->dev.of_node) { + const struct of_device_id *match; + match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node); + if (!match) + return NULL; + return (struct at91_twi_pdata *)match->data; + } + return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data; +} + +static int at91_twi_probe(struct platform_device *pdev) +{ + struct at91_twi_dev *dev; + struct resource *mem; + int rc; + u32 phy_addr; + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->dev = &pdev->dev; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) + return -ENODEV; + phy_addr = mem->start; + + dev->pdata = at91_twi_get_driver_data(pdev); + if (!dev->pdata) + return -ENODEV; + + dev->base = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(dev->base)) + return PTR_ERR(dev->base); + + dev->irq = platform_get_irq(pdev, 0); + if (dev->irq < 0) + return dev->irq; + + platform_set_drvdata(pdev, dev); + + dev->clk = devm_clk_get(dev->dev, NULL); + if (IS_ERR(dev->clk)) { + dev_err(dev->dev, "no clock defined\n"); + return -ENODEV; + } + clk_prepare_enable(dev->clk); + + snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91"); + i2c_set_adapdata(&dev->adapter, dev); + dev->adapter.owner = THIS_MODULE; + dev->adapter.class = I2C_CLASS_DEPRECATED; + dev->adapter.dev.parent = dev->dev; + dev->adapter.nr = pdev->id; + dev->adapter.timeout = AT91_I2C_TIMEOUT; + dev->adapter.dev.of_node = pdev->dev.of_node; + + rc = at91_twi_probe_master(pdev, phy_addr, dev); + if (rc) + return rc; + + at91_init_twi_bus(dev); + + pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT); + pm_runtime_use_autosuspend(dev->dev); + pm_runtime_set_active(dev->dev); + pm_runtime_enable(dev->dev); + + rc = i2c_add_numbered_adapter(&dev->adapter); + if (rc) { + clk_disable_unprepare(dev->clk); + + pm_runtime_disable(dev->dev); + pm_runtime_set_suspended(dev->dev); + + return rc; + } + + dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n", + at91_twi_read(dev, AT91_TWI_VER)); + return 0; +} + +static int at91_twi_remove(struct platform_device *pdev) +{ + struct at91_twi_dev *dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&dev->adapter); + clk_disable_unprepare(dev->clk); + + pm_runtime_disable(dev->dev); + pm_runtime_set_suspended(dev->dev); + + return 0; +} + +#ifdef CONFIG_PM + +static int at91_twi_runtime_suspend(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + + clk_disable_unprepare(twi_dev->clk); + + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int at91_twi_runtime_resume(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + + pinctrl_pm_select_default_state(dev); + + return clk_prepare_enable(twi_dev->clk); +} + +static int at91_twi_suspend_noirq(struct device *dev) +{ + if (!pm_runtime_status_suspended(dev)) + at91_twi_runtime_suspend(dev); + + return 0; +} + +static int at91_twi_resume_noirq(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + int ret; + + if (!pm_runtime_status_suspended(dev)) { + ret = at91_twi_runtime_resume(dev); + if (ret) + return ret; + } + + pm_runtime_mark_last_busy(dev); + pm_request_autosuspend(dev); + + at91_init_twi_bus(twi_dev); + + return 0; +} + +static const struct dev_pm_ops at91_twi_pm = { + .suspend_noirq = at91_twi_suspend_noirq, + .resume_noirq = at91_twi_resume_noirq, + .runtime_suspend = at91_twi_runtime_suspend, + .runtime_resume = at91_twi_runtime_resume, +}; + +#define at91_twi_pm_ops (&at91_twi_pm) +#else +#define at91_twi_pm_ops NULL +#endif + +static struct platform_driver at91_twi_driver = { + .probe = at91_twi_probe, + .remove = at91_twi_remove, + .id_table = at91_twi_devtypes, + .driver = { + .name = "at91_i2c", + .of_match_table = of_match_ptr(atmel_twi_dt_ids), + .pm = at91_twi_pm_ops, + }, +}; + +static int __init at91_twi_init(void) +{ + return platform_driver_register(&at91_twi_driver); +} + +static void __exit at91_twi_exit(void) +{ + platform_driver_unregister(&at91_twi_driver); +} + +subsys_initcall(at91_twi_init); +module_exit(at91_twi_exit); + +MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>"); +MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:at91_i2c"); diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91-master.c index bc74184462c6..2fca78711f81 100644 --- a/drivers/i2c/busses/i2c-at91.c +++ b/drivers/i2c/busses/i2c-at91-master.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) * @@ -10,11 +11,6 @@ * * Borrowed heavily from original work by: * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. */ #include <linux/clk.h> @@ -25,156 +21,15 @@ #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/io.h> -#include <linux/module.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/platform_device.h> -#include <linux/slab.h> #include <linux/platform_data/dma-atmel.h> #include <linux/pm_runtime.h> -#include <linux/pinctrl/consumer.h> - -#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */ -#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */ -#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */ -#define AUTOSUSPEND_TIMEOUT 2000 -#define AT91_I2C_MAX_ALT_CMD_DATA_SIZE 256 - -/* AT91 TWI register definitions */ -#define AT91_TWI_CR 0x0000 /* Control Register */ -#define AT91_TWI_START BIT(0) /* Send a Start Condition */ -#define AT91_TWI_STOP BIT(1) /* Send a Stop Condition */ -#define AT91_TWI_MSEN BIT(2) /* Master Transfer Enable */ -#define AT91_TWI_MSDIS BIT(3) /* Master Transfer Disable */ -#define AT91_TWI_SVEN BIT(4) /* Slave Transfer Enable */ -#define AT91_TWI_SVDIS BIT(5) /* Slave Transfer Disable */ -#define AT91_TWI_QUICK BIT(6) /* SMBus quick command */ -#define AT91_TWI_SWRST BIT(7) /* Software Reset */ -#define AT91_TWI_ACMEN BIT(16) /* Alternative Command Mode Enable */ -#define AT91_TWI_ACMDIS BIT(17) /* Alternative Command Mode Disable */ -#define AT91_TWI_THRCLR BIT(24) /* Transmit Holding Register Clear */ -#define AT91_TWI_RHRCLR BIT(25) /* Receive Holding Register Clear */ -#define AT91_TWI_LOCKCLR BIT(26) /* Lock Clear */ -#define AT91_TWI_FIFOEN BIT(28) /* FIFO Enable */ -#define AT91_TWI_FIFODIS BIT(29) /* FIFO Disable */ - -#define AT91_TWI_MMR 0x0004 /* Master Mode Register */ -#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */ -#define AT91_TWI_MREAD BIT(12) /* Master Read Direction */ - -#define AT91_TWI_IADR 0x000c /* Internal Address Register */ - -#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */ -#define AT91_TWI_CWGR_HOLD_MAX 0x1f -#define AT91_TWI_CWGR_HOLD(x) (((x) & AT91_TWI_CWGR_HOLD_MAX) << 24) - -#define AT91_TWI_SR 0x0020 /* Status Register */ -#define AT91_TWI_TXCOMP BIT(0) /* Transmission Complete */ -#define AT91_TWI_RXRDY BIT(1) /* Receive Holding Register Ready */ -#define AT91_TWI_TXRDY BIT(2) /* Transmit Holding Register Ready */ -#define AT91_TWI_OVRE BIT(6) /* Overrun Error */ -#define AT91_TWI_UNRE BIT(7) /* Underrun Error */ -#define AT91_TWI_NACK BIT(8) /* Not Acknowledged */ -#define AT91_TWI_LOCK BIT(23) /* TWI Lock due to Frame Errors */ - -#define AT91_TWI_INT_MASK \ - (AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY | AT91_TWI_NACK) - -#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */ -#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */ -#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */ -#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */ -#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */ - -#define AT91_TWI_ACR 0x0040 /* Alternative Command Register */ -#define AT91_TWI_ACR_DATAL(len) ((len) & 0xff) -#define AT91_TWI_ACR_DIR BIT(8) - -#define AT91_TWI_FMR 0x0050 /* FIFO Mode Register */ -#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0) -#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0) -#define AT91_TWI_FMR_RXRDYM(mode) (((mode) & 0x3) << 4) -#define AT91_TWI_FMR_RXRDYM_MASK (0x3 << 4) -#define AT91_TWI_ONE_DATA 0x0 -#define AT91_TWI_TWO_DATA 0x1 -#define AT91_TWI_FOUR_DATA 0x2 - -#define AT91_TWI_FLR 0x0054 /* FIFO Level Register */ - -#define AT91_TWI_FSR 0x0060 /* FIFO Status Register */ -#define AT91_TWI_FIER 0x0064 /* FIFO Interrupt Enable Register */ -#define AT91_TWI_FIDR 0x0068 /* FIFO Interrupt Disable Register */ -#define AT91_TWI_FIMR 0x006c /* FIFO Interrupt Mask Register */ - -#define AT91_TWI_VER 0x00fc /* Version Register */ - -struct at91_twi_pdata { - unsigned clk_max_div; - unsigned clk_offset; - bool has_unre_flag; - bool has_alt_cmd; - bool has_hold_field; - struct at_dma_slave dma_slave; -}; - -struct at91_twi_dma { - struct dma_chan *chan_rx; - struct dma_chan *chan_tx; - struct scatterlist sg[2]; - struct dma_async_tx_descriptor *data_desc; - enum dma_data_direction direction; - bool buf_mapped; - bool xfer_in_progress; -}; - -struct at91_twi_dev { - struct device *dev; - void __iomem *base; - struct completion cmd_complete; - struct clk *clk; - u8 *buf; - size_t buf_len; - struct i2c_msg *msg; - int irq; - unsigned imr; - unsigned transfer_status; - struct i2c_adapter adapter; - unsigned twi_cwgr_reg; - struct at91_twi_pdata *pdata; - bool use_dma; - bool use_alt_cmd; - bool recv_len_abort; - u32 fifo_size; - struct at91_twi_dma dma; -}; - -static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg) -{ - return readl_relaxed(dev->base + reg); -} - -static void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val) -{ - writel_relaxed(val, dev->base + reg); -} - -static void at91_disable_twi_interrupts(struct at91_twi_dev *dev) -{ - at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK); -} -static void at91_twi_irq_save(struct at91_twi_dev *dev) -{ - dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK; - at91_disable_twi_interrupts(dev); -} - -static void at91_twi_irq_restore(struct at91_twi_dev *dev) -{ - at91_twi_write(dev, AT91_TWI_IER, dev->imr); -} +#include "i2c-at91.h" -static void at91_init_twi_bus_master(struct at91_twi_dev *dev) +void at91_init_twi_bus_master(struct at91_twi_dev *dev) { /* FIFO should be enabled immediately after the software reset */ if (dev->fifo_size) @@ -184,14 +39,6 @@ static void at91_init_twi_bus_master(struct at91_twi_dev *dev) at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg); } -static void at91_init_twi_bus(struct at91_twi_dev *dev) -{ - at91_disable_twi_interrupts(dev); - at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST); - - at91_init_twi_bus_master(dev); -} - /* * Calculate symmetric clock as stated in datasheet: * twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset)) @@ -839,124 +686,6 @@ static const struct i2c_algorithm at91_twi_algorithm = { .functionality = at91_twi_func, }; -static struct at91_twi_pdata at91rm9200_config = { - .clk_max_div = 5, - .clk_offset = 3, - .has_unre_flag = true, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static struct at91_twi_pdata at91sam9261_config = { - .clk_max_div = 5, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static struct at91_twi_pdata at91sam9260_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static struct at91_twi_pdata at91sam9g20_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static struct at91_twi_pdata at91sam9g10_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static const struct platform_device_id at91_twi_devtypes[] = { - { - .name = "i2c-at91rm9200", - .driver_data = (unsigned long) &at91rm9200_config, - }, { - .name = "i2c-at91sam9261", - .driver_data = (unsigned long) &at91sam9261_config, - }, { - .name = "i2c-at91sam9260", - .driver_data = (unsigned long) &at91sam9260_config, - }, { - .name = "i2c-at91sam9g20", - .driver_data = (unsigned long) &at91sam9g20_config, - }, { - .name = "i2c-at91sam9g10", - .driver_data = (unsigned long) &at91sam9g10_config, - }, { - /* sentinel */ - } -}; - -#if defined(CONFIG_OF) -static struct at91_twi_pdata at91sam9x5_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = false, -}; - -static struct at91_twi_pdata sama5d4_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = false, - .has_alt_cmd = false, - .has_hold_field = true, -}; - -static struct at91_twi_pdata sama5d2_config = { - .clk_max_div = 7, - .clk_offset = 4, - .has_unre_flag = true, - .has_alt_cmd = true, - .has_hold_field = true, -}; - -static const struct of_device_id atmel_twi_dt_ids[] = { - { - .compatible = "atmel,at91rm9200-i2c", - .data = &at91rm9200_config, - } , { - .compatible = "atmel,at91sam9260-i2c", - .data = &at91sam9260_config, - } , { - .compatible = "atmel,at91sam9261-i2c", - .data = &at91sam9261_config, - } , { - .compatible = "atmel,at91sam9g20-i2c", - .data = &at91sam9g20_config, - } , { - .compatible = "atmel,at91sam9g10-i2c", - .data = &at91sam9g10_config, - }, { - .compatible = "atmel,at91sam9x5-i2c", - .data = &at91sam9x5_config, - }, { - .compatible = "atmel,sama5d4-i2c", - .data = &sama5d4_config, - }, { - .compatible = "atmel,sama5d2-i2c", - .data = &sama5d2_config, - }, { - /* sentinel */ - } -}; -MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids); -#endif - static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) { int ret = 0; @@ -1039,21 +768,8 @@ error: return ret; } -static struct at91_twi_pdata *at91_twi_get_driver_data( - struct platform_device *pdev) -{ - if (pdev->dev.of_node) { - const struct of_device_id *match; - match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node); - if (!match) - return NULL; - return (struct at91_twi_pdata *)match->data; - } - return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data; -} - -static int at91_twi_probe_master(struct platform_device *pdev, - u32 phy_addr, struct at91_twi_dev *dev) +int at91_twi_probe_master(struct platform_device *pdev, + u32 phy_addr, struct at91_twi_dev *dev) { int rc; u32 bus_clk_rate; @@ -1090,182 +806,3 @@ static int at91_twi_probe_master(struct platform_device *pdev, return 0; } - -static int at91_twi_probe(struct platform_device *pdev) -{ - struct at91_twi_dev *dev; - struct resource *mem; - int rc; - u32 phy_addr; - - dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); - if (!dev) - return -ENOMEM; - - dev->dev = &pdev->dev; - - mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!mem) - return -ENODEV; - phy_addr = mem->start; - - dev->pdata = at91_twi_get_driver_data(pdev); - if (!dev->pdata) - return -ENODEV; - - dev->base = devm_ioremap_resource(&pdev->dev, mem); - if (IS_ERR(dev->base)) - return PTR_ERR(dev->base); - - dev->irq = platform_get_irq(pdev, 0); - if (dev->irq < 0) - return dev->irq; - - platform_set_drvdata(pdev, dev); - - dev->clk = devm_clk_get(dev->dev, NULL); - if (IS_ERR(dev->clk)) { - dev_err(dev->dev, "no clock defined\n"); - return -ENODEV; - } - rc = clk_prepare_enable(dev->clk); - if (rc) - return rc; - - snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91"); - i2c_set_adapdata(&dev->adapter, dev); - dev->adapter.owner = THIS_MODULE; - dev->adapter.class = I2C_CLASS_DEPRECATED; - dev->adapter.dev.parent = dev->dev; - dev->adapter.nr = pdev->id; - dev->adapter.timeout = AT91_I2C_TIMEOUT; - dev->adapter.dev.of_node = pdev->dev.of_node; - - rc = at91_twi_probe_master(pdev, phy_addr, dev); - if (rc) - return rc; - - at91_init_twi_bus(dev); - - pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT); - pm_runtime_use_autosuspend(dev->dev); - pm_runtime_set_active(dev->dev); - pm_runtime_enable(dev->dev); - - rc = i2c_add_numbered_adapter(&dev->adapter); - if (rc) { - clk_disable_unprepare(dev->clk); - - pm_runtime_disable(dev->dev); - pm_runtime_set_suspended(dev->dev); - - return rc; - } - - dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n", - at91_twi_read(dev, AT91_TWI_VER)); - return 0; -} - -static int at91_twi_remove(struct platform_device *pdev) -{ - struct at91_twi_dev *dev = platform_get_drvdata(pdev); - - i2c_del_adapter(&dev->adapter); - clk_disable_unprepare(dev->clk); - - pm_runtime_disable(dev->dev); - pm_runtime_set_suspended(dev->dev); - - return 0; -} - -#ifdef CONFIG_PM - -static int at91_twi_runtime_suspend(struct device *dev) -{ - struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); - - clk_disable_unprepare(twi_dev->clk); - - pinctrl_pm_select_sleep_state(dev); - - return 0; -} - -static int at91_twi_runtime_resume(struct device *dev) -{ - struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); - - pinctrl_pm_select_default_state(dev); - - return clk_prepare_enable(twi_dev->clk); -} - -static int at91_twi_suspend_noirq(struct device *dev) -{ - if (!pm_runtime_status_suspended(dev)) - at91_twi_runtime_suspend(dev); - - return 0; -} - -static int at91_twi_resume_noirq(struct device *dev) -{ - struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); - int ret; - - if (!pm_runtime_status_suspended(dev)) { - ret = at91_twi_runtime_resume(dev); - if (ret) - return ret; - } - - pm_runtime_mark_last_busy(dev); - pm_request_autosuspend(dev); - - at91_init_twi_bus(twi_dev); - - return 0; -} - -static const struct dev_pm_ops at91_twi_pm = { - .suspend_noirq = at91_twi_suspend_noirq, - .resume_noirq = at91_twi_resume_noirq, - .runtime_suspend = at91_twi_runtime_suspend, - .runtime_resume = at91_twi_runtime_resume, -}; - -#define at91_twi_pm_ops (&at91_twi_pm) -#else -#define at91_twi_pm_ops NULL -#endif - -static struct platform_driver at91_twi_driver = { - .probe = at91_twi_probe, - .remove = at91_twi_remove, - .id_table = at91_twi_devtypes, - .driver = { - .name = "at91_i2c", - .of_match_table = of_match_ptr(atmel_twi_dt_ids), - .pm = at91_twi_pm_ops, - }, -}; - -static int __init at91_twi_init(void) -{ - return platform_driver_register(&at91_twi_driver); -} - -static void __exit at91_twi_exit(void) -{ - platform_driver_unregister(&at91_twi_driver); -} - -subsys_initcall(at91_twi_init); -module_exit(at91_twi_exit); - -MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>"); -MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:at91_i2c"); diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h new file mode 100644 index 000000000000..636447498b41 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91.h @@ -0,0 +1,147 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2011 Weinmann Medical GmbH + * Author: Nikolaus Voss <n.voss@weinmann.de> + * + * Evolved from original work by: + * Copyright (C) 2004 Rick Bronson + * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com> + * + * Borrowed heavily from original work by: + * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/i2c.h> +#include <linux/platform_data/dma-atmel.h> +#include <linux/platform_device.h> + +#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */ +#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */ +#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */ +#define AUTOSUSPEND_TIMEOUT 2000 +#define AT91_I2C_MAX_ALT_CMD_DATA_SIZE 256 + +/* AT91 TWI register definitions */ +#define AT91_TWI_CR 0x0000 /* Control Register */ +#define AT91_TWI_START BIT(0) /* Send a Start Condition */ +#define AT91_TWI_STOP BIT(1) /* Send a Stop Condition */ +#define AT91_TWI_MSEN BIT(2) /* Master Transfer Enable */ +#define AT91_TWI_MSDIS BIT(3) /* Master Transfer Disable */ +#define AT91_TWI_SVEN BIT(4) /* Slave Transfer Enable */ +#define AT91_TWI_SVDIS BIT(5) /* Slave Transfer Disable */ +#define AT91_TWI_QUICK BIT(6) /* SMBus quick command */ +#define AT91_TWI_SWRST BIT(7) /* Software Reset */ +#define AT91_TWI_ACMEN BIT(16) /* Alternative Command Mode Enable */ +#define AT91_TWI_ACMDIS BIT(17) /* Alternative Command Mode Disable */ +#define AT91_TWI_THRCLR BIT(24) /* Transmit Holding Register Clear */ +#define AT91_TWI_RHRCLR BIT(25) /* Receive Holding Register Clear */ +#define AT91_TWI_LOCKCLR BIT(26) /* Lock Clear */ +#define AT91_TWI_FIFOEN BIT(28) /* FIFO Enable */ +#define AT91_TWI_FIFODIS BIT(29) /* FIFO Disable */ + +#define AT91_TWI_MMR 0x0004 /* Master Mode Register */ +#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */ +#define AT91_TWI_MREAD BIT(12) /* Master Read Direction */ + +#define AT91_TWI_IADR 0x000c /* Internal Address Register */ + +#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */ +#define AT91_TWI_CWGR_HOLD_MAX 0x1f +#define AT91_TWI_CWGR_HOLD(x) (((x) & AT91_TWI_CWGR_HOLD_MAX) << 24) + +#define AT91_TWI_SR 0x0020 /* Status Register */ +#define AT91_TWI_TXCOMP BIT(0) /* Transmission Complete */ +#define AT91_TWI_RXRDY BIT(1) /* Receive Holding Register Ready */ +#define AT91_TWI_TXRDY BIT(2) /* Transmit Holding Register Ready */ +#define AT91_TWI_OVRE BIT(6) /* Overrun Error */ +#define AT91_TWI_UNRE BIT(7) /* Underrun Error */ +#define AT91_TWI_NACK BIT(8) /* Not Acknowledged */ +#define AT91_TWI_LOCK BIT(23) /* TWI Lock due to Frame Errors */ + +#define AT91_TWI_INT_MASK \ + (AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY | AT91_TWI_NACK) + +#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */ +#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */ +#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */ +#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */ +#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */ + +#define AT91_TWI_ACR 0x0040 /* Alternative Command Register */ +#define AT91_TWI_ACR_DATAL(len) ((len) & 0xff) +#define AT91_TWI_ACR_DIR BIT(8) + +#define AT91_TWI_FMR 0x0050 /* FIFO Mode Register */ +#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0) +#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0) +#define AT91_TWI_FMR_RXRDYM(mode) (((mode) & 0x3) << 4) +#define AT91_TWI_FMR_RXRDYM_MASK (0x3 << 4) +#define AT91_TWI_ONE_DATA 0x0 +#define AT91_TWI_TWO_DATA 0x1 +#define AT91_TWI_FOUR_DATA 0x2 + +#define AT91_TWI_FLR 0x0054 /* FIFO Level Register */ + +#define AT91_TWI_FSR 0x0060 /* FIFO Status Register */ +#define AT91_TWI_FIER 0x0064 /* FIFO Interrupt Enable Register */ +#define AT91_TWI_FIDR 0x0068 /* FIFO Interrupt Disable Register */ +#define AT91_TWI_FIMR 0x006c /* FIFO Interrupt Mask Register */ + +#define AT91_TWI_VER 0x00fc /* Version Register */ + +struct at91_twi_pdata { + unsigned clk_max_div; + unsigned clk_offset; + bool has_unre_flag; + bool has_alt_cmd; + bool has_hold_field; + struct at_dma_slave dma_slave; +}; + +struct at91_twi_dma { + struct dma_chan *chan_rx; + struct dma_chan *chan_tx; + struct scatterlist sg[2]; + struct dma_async_tx_descriptor *data_desc; + enum dma_data_direction direction; + bool buf_mapped; + bool xfer_in_progress; +}; + +struct at91_twi_dev { + struct device *dev; + void __iomem *base; + struct completion cmd_complete; + struct clk *clk; + u8 *buf; + size_t buf_len; + struct i2c_msg *msg; + int irq; + unsigned imr; + unsigned transfer_status; + struct i2c_adapter adapter; + unsigned twi_cwgr_reg; + struct at91_twi_pdata *pdata; + bool use_dma; + bool use_alt_cmd; + bool recv_len_abort; + u32 fifo_size; + struct at91_twi_dma dma; +}; + +unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg); +void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val); +void at91_disable_twi_interrupts(struct at91_twi_dev *dev); +void at91_twi_irq_save(struct at91_twi_dev *dev); +void at91_twi_irq_restore(struct at91_twi_dev *dev); +void at91_init_twi_bus(struct at91_twi_dev *dev); + +void at91_init_twi_bus_master(struct at91_twi_dev *dev); +int at91_twi_probe_master(struct platform_device *pdev, u32 phy_addr, + struct at91_twi_dev *dev); |