Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755321AbYJFTng (ORCPT ); Mon, 6 Oct 2008 15:43:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752850AbYJFTnO (ORCPT ); Mon, 6 Oct 2008 15:43:14 -0400 Received: from mail-gx0-f16.google.com ([209.85.217.16]:55311 "EHLO mail-gx0-f16.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752589AbYJFTnM (ORCPT ); Mon, 6 Oct 2008 15:43:12 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:subject:to:date:message-id:in-reply-to:references:user-agent :mime-version:content-type:content-transfer-encoding; b=gTYg6GAtgt7kDjM1bMfZYfiX0lBEH2c4T2VogMBuNFZpaErc55ugxOuQruFH/MIDOh hyUGGE34aDNcTi0/c37+JlkTIpbIBoKAlQ/bY8gMdmnG4FTjm3MQMTv1EHEQpfLI3GEe YYiDDKkSzWx5P1Cx112flWNU792itcZheXmdE= From: Jon Smirl Subject: [RFC PATCH 2/4] GPT driver for in-kernel IR support. To: linux-kernel@vger.kernel.org, lirc-list@lists.sourceforge.net Date: Mon, 06 Oct 2008 15:43:10 -0400 Message-ID: <20081006194310.15992.71553.stgit@terra> In-Reply-To: <20081006194032.15992.8393.stgit@terra> References: <20081006194032.15992.8393.stgit@terra> User-Agent: StGIT/0.14.3.224.g199b MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6826 Lines: 266 GPT is a GPIO pin that is cable able of measuring the lenght of pulses. GPTs are common on embedded systems --- drivers/input/ir/Kconfig | 6 + drivers/input/ir/Makefile | 1 drivers/input/ir/ir-gpt.c | 221 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 228 insertions(+), 0 deletions(-) create mode 100644 drivers/input/ir/ir-gpt.c diff --git a/drivers/input/ir/Kconfig b/drivers/input/ir/Kconfig index 8afd2d6..b80ab31 100644 --- a/drivers/input/ir/Kconfig +++ b/drivers/input/ir/Kconfig @@ -11,4 +11,10 @@ menuconfig INPUT_IR if INPUT_IR +config IR_GPT + tristate "GPT Based IR Receiver" + default m + help + Driver for GPT-based IR receiver found on Digispeaker + endif diff --git a/drivers/input/ir/Makefile b/drivers/input/ir/Makefile index 08e6954..7082f1d 100644 --- a/drivers/input/ir/Makefile +++ b/drivers/input/ir/Makefile @@ -3,3 +3,4 @@ # Each configuration option enables a list of files. +obj-$(CONFIG_IR_GPT) += ir-gpt.o diff --git a/drivers/input/ir/ir-gpt.c b/drivers/input/ir/ir-gpt.c new file mode 100644 index 0000000..a26abe9 --- /dev/null +++ b/drivers/input/ir/ir-gpt.c @@ -0,0 +1,221 @@ +/* + * GPT timer based IR device + * + * Copyright (C) 2008 Jon Smirl + */ + +#define DEBUG + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAX_SAMPLES 200 + +struct ir_gpt { + int irq; + struct mpc52xx_gpt __iomem *regs; + spinlock_t lock; + struct work_struct queue; + int head, tail, previous; + unsigned int samples[MAX_SAMPLES]; + struct input_dev *input; +}; + +static void ir_event(struct work_struct *work) +{ + unsigned long flags; + int delta, count; + unsigned int sample, wrap, bit; + struct ir_gpt *ir_gpt = container_of(work, struct ir_gpt, queue); + + while (1) { + spin_lock_irqsave(ir_gpt->lock, flags); + if (ir_gpt->tail == ir_gpt->head) { + spin_unlock_irqrestore(ir_gpt->lock, flags); + break; + } + sample = ir_gpt->samples[ir_gpt->tail]; + + ir_gpt->tail++; + if (ir_gpt->tail >= MAX_SAMPLES) + ir_gpt->tail = 0; + + spin_unlock_irqrestore(ir_gpt->lock, flags); + + count = sample >> 16; + wrap = (sample >> 12) & 7; + bit = (sample >> 8) & 1; + + delta = count - ir_gpt->previous; + delta += wrap * 0x10000; + + ir_gpt->previous = count; + + input_ir_decode(ir_gpt->input, delta, bit); + } +} + +/* + * Interrupt handlers + */ +static irqreturn_t dpeak_ir_irq(int irq, void *_ir) +{ + unsigned long flags; + unsigned int sample, next; + struct ir_gpt *ir_gpt = _ir; + + sample = in_be32(&ir_gpt->regs->status); + out_be32(&ir_gpt->regs->status, 0xF); + + spin_lock_irqsave(ir_gpt->lock, flags); + ir_gpt->samples[ir_gpt->head] = sample; + next = ir_gpt->head + 1; + ir_gpt->head = (next >= MAX_SAMPLES ? 0 : next); + spin_unlock_irqrestore(ir_gpt->lock, flags); + + schedule_work(&ir_gpt->queue); + + return IRQ_HANDLED; +} + + +/* --------------------------------------------------------------------- + * OF platform bus binding code: + * - Probe/remove operations + * - OF device match table + */ +static int __devinit ir_gpt_of_probe(struct of_device *op, + const struct of_device_id *match) +{ + struct ir_gpt *ir_gpt; + struct resource res; + int ret, rc; + + dev_dbg(&op->dev, "ir_gpt_of_probe\n"); + + /* Allocate and initialize the driver private data */ + ir_gpt = kzalloc(sizeof *ir_gpt, GFP_KERNEL); + if (!ir_gpt) + return -ENOMEM; + + ir_gpt->input = input_allocate_device(); + if (!ir_gpt->input) { + ret = -ENOMEM; + goto free_mem; + } + ret = input_ir_create(ir_gpt->input, ir_gpt, NULL); + if (ret) + goto free_input; + + ir_gpt->input->id.bustype = BUS_HOST; + ir_gpt->input->name = "GPT IR Receiver"; + + ir_gpt->input->irbit[0] |= BIT_MASK(IR_CAP_RECEIVE_36K); + ir_gpt->input->irbit[0] |= BIT_MASK(IR_CAP_RECEIVE_38K); + ir_gpt->input->irbit[0] |= BIT_MASK(IR_CAP_RECEIVE_40K); + ir_gpt->input->irbit[0] |= BIT_MASK(IR_CAP_RECEIVE_RAW); + + ret = input_register_device(ir_gpt->input); + if (ret) + goto free_input; + + spin_lock_init(&ir_gpt->lock); + INIT_WORK (&ir_gpt->queue, ir_event); + + /* Fetch the registers and IRQ of the GPT */ + if (of_address_to_resource(op->node, 0, &res)) { + dev_err(&op->dev, "Missing reg property\n"); + ret = -ENODEV; + goto free_input; + } + ir_gpt->regs = ioremap(res.start, 1 + res.end - res.start); + if (!ir_gpt->regs) { + dev_err(&op->dev, "Could not map registers\n"); + ret = -ENODEV; + goto free_input; + } + ir_gpt->irq = irq_of_parse_and_map(op->node, 0); + if (ir_gpt->irq == NO_IRQ) { + ret = -ENODEV; + goto free_input; + } + dev_dbg(&op->dev, "ir_gpt_of_probe irq=%d\n", ir_gpt->irq); + + rc = request_irq(ir_gpt->irq, &dpeak_ir_irq, IRQF_SHARED, + "gpt-ir", ir_gpt); + dev_dbg(&op->dev, "ir_gpt_of_probe request irq rc=%d\n", rc); + + /* set prescale to ? */ + out_be32(&ir_gpt->regs->count, 0x00870000); + + /* Select input capture, enable the counter, and interrupt */ + out_be32(&ir_gpt->regs->mode, 0x0); + out_be32(&ir_gpt->regs->mode, 0x00000501); + + /* Save what we've done so it can be found again later */ + dev_set_drvdata(&op->dev, ir_gpt); + + printk("GPT IR Receiver driver\n"); + + return 0; + +free_input: + input_ir_destroy(ir_gpt->input); + input_free_device(ir_gpt->input); +free_mem: + kfree(ir_gpt); + return ret; +} + +static int __devexit ir_gpt_of_remove(struct of_device *op) +{ + struct ir_gpt *ir_gpt = dev_get_drvdata(&op->dev); + + dev_dbg(&op->dev, "ir_gpt_remove()\n"); + + input_ir_destroy(ir_gpt->input); + input_free_device(ir_gpt->input); + kfree(ir_gpt); + dev_set_drvdata(&op->dev, NULL); + + return 0; +} + +/* Match table for of_platform binding */ +static struct of_device_id ir_gpt_match[] __devinitdata = { + { .compatible = "gpt-ir", }, + {} +}; +MODULE_DEVICE_TABLE(of, ir_gpt_match); + +static struct of_platform_driver ir_gpt_driver = { + .match_table = ir_gpt_match, + .probe = ir_gpt_of_probe, + .remove = __devexit_p(ir_gpt_of_remove), + .driver = { + .name = "ir-gpt", + .owner = THIS_MODULE, + }, +}; + +/* --------------------------------------------------------------------- + * Module setup and teardown; simply register the of_platform driver + */ +static int __init ir_gpt_init(void) +{ + return of_register_platform_driver(&ir_gpt_driver); +} +module_init(ir_gpt_init); + +static void __exit ir_gpt_exit(void) +{ + of_unregister_platform_driver(&ir_gpt_driver); +} +module_exit(ir_gpt_exit); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/