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authorIngo Molnar <mingo@kernel.org>2017-03-01 09:02:26 +0100
committerIngo Molnar <mingo@kernel.org>2017-03-01 09:02:26 +0100
commit0871d5a66da5c41151e0896a90298b163e42f2e0 (patch)
tree1ba71fab9016cb28bb9d18ffd62b6b744f2f761c /drivers/media/rc/ir-spi.c
parentx86/boot: Fix pr_debug() API braindamage (diff)
parentMerge tag 'for-linus-4.11' of git://git.code.sf.net/p/openipmi/linux-ipmi (diff)
downloadlinux-0871d5a66da5c41151e0896a90298b163e42f2e0.tar.xz
linux-0871d5a66da5c41151e0896a90298b163e42f2e0.zip
Merge branch 'linus' into WIP.x86/boot, to fix up conflicts and to pick up updates
Conflicts: arch/x86/xen/setup.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/media/rc/ir-spi.c')
-rw-r--r--drivers/media/rc/ir-spi.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-spi.c b/drivers/media/rc/ir-spi.c
new file mode 100644
index 000000000000..c8863f36686a
--- /dev/null
+++ b/drivers/media/rc/ir-spi.c
@@ -0,0 +1,199 @@
+/*
+ * Copyright (c) 2016 Samsung Electronics Co., Ltd.
+ * Author: Andi Shyti <andi.shyti@samsung.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.
+ *
+ * SPI driven IR LED device driver
+ */
+
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_gpio.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <media/rc-core.h>
+
+#define IR_SPI_DRIVER_NAME "ir-spi"
+
+/* pulse value for different duty cycles */
+#define IR_SPI_PULSE_DC_50 0xff00
+#define IR_SPI_PULSE_DC_60 0xfc00
+#define IR_SPI_PULSE_DC_70 0xf800
+#define IR_SPI_PULSE_DC_75 0xf000
+#define IR_SPI_PULSE_DC_80 0xc000
+#define IR_SPI_PULSE_DC_90 0x8000
+
+#define IR_SPI_DEFAULT_FREQUENCY 38000
+#define IR_SPI_BIT_PER_WORD 8
+#define IR_SPI_MAX_BUFSIZE 4096
+
+struct ir_spi_data {
+ u32 freq;
+ u8 duty_cycle;
+ bool negated;
+
+ u16 tx_buf[IR_SPI_MAX_BUFSIZE];
+ u16 pulse;
+ u16 space;
+
+ struct rc_dev *rc;
+ struct spi_device *spi;
+ struct regulator *regulator;
+};
+
+static int ir_spi_tx(struct rc_dev *dev,
+ unsigned int *buffer, unsigned int count)
+{
+ int i;
+ int ret;
+ unsigned int len = 0;
+ struct ir_spi_data *idata = dev->priv;
+ struct spi_transfer xfer;
+
+ /* convert the pulse/space signal to raw binary signal */
+ for (i = 0; i < count; i++) {
+ int j;
+ u16 val = ((i + 1) % 2) ? idata->pulse : idata->space;
+
+ if (len + buffer[i] >= IR_SPI_MAX_BUFSIZE)
+ return -EINVAL;
+
+ /*
+ * the first value in buffer is a pulse, so that 0, 2, 4, ...
+ * contain a pulse duration. On the contrary, 1, 3, 5, ...
+ * contain a space duration.
+ */
+ val = (i % 2) ? idata->space : idata->pulse;
+ for (j = 0; j < buffer[i]; j++)
+ idata->tx_buf[len++] = val;
+ }
+
+ memset(&xfer, 0, sizeof(xfer));
+
+ xfer.speed_hz = idata->freq;
+ xfer.len = len * sizeof(*idata->tx_buf);
+ xfer.tx_buf = idata->tx_buf;
+
+ ret = regulator_enable(idata->regulator);
+ if (ret)
+ return ret;
+
+ ret = spi_sync_transfer(idata->spi, &xfer, 1);
+ if (ret)
+ dev_err(&idata->spi->dev, "unable to deliver the signal\n");
+
+ regulator_disable(idata->regulator);
+
+ return ret ? ret : count;
+}
+
+static int ir_spi_set_tx_carrier(struct rc_dev *dev, u32 carrier)
+{
+ struct ir_spi_data *idata = dev->priv;
+
+ if (!carrier)
+ return -EINVAL;
+
+ idata->freq = carrier;
+
+ return 0;
+}
+
+static int ir_spi_set_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
+{
+ struct ir_spi_data *idata = dev->priv;
+
+ if (duty_cycle >= 90)
+ idata->pulse = IR_SPI_PULSE_DC_90;
+ else if (duty_cycle >= 80)
+ idata->pulse = IR_SPI_PULSE_DC_80;
+ else if (duty_cycle >= 75)
+ idata->pulse = IR_SPI_PULSE_DC_75;
+ else if (duty_cycle >= 70)
+ idata->pulse = IR_SPI_PULSE_DC_70;
+ else if (duty_cycle >= 60)
+ idata->pulse = IR_SPI_PULSE_DC_60;
+ else
+ idata->pulse = IR_SPI_PULSE_DC_50;
+
+ if (idata->negated) {
+ idata->pulse = ~idata->pulse;
+ idata->space = 0xffff;
+ } else {
+ idata->space = 0;
+ }
+
+ return 0;
+}
+
+static int ir_spi_probe(struct spi_device *spi)
+{
+ int ret;
+ u8 dc;
+ struct ir_spi_data *idata;
+
+ idata = devm_kzalloc(&spi->dev, sizeof(*idata), GFP_KERNEL);
+ if (!idata)
+ return -ENOMEM;
+
+ idata->regulator = devm_regulator_get(&spi->dev, "irda_regulator");
+ if (IS_ERR(idata->regulator))
+ return PTR_ERR(idata->regulator);
+
+ idata->rc = devm_rc_allocate_device(&spi->dev, RC_DRIVER_IR_RAW_TX);
+ if (!idata->rc)
+ return -ENOMEM;
+
+ idata->rc->tx_ir = ir_spi_tx;
+ idata->rc->s_tx_carrier = ir_spi_set_tx_carrier;
+ idata->rc->s_tx_duty_cycle = ir_spi_set_duty_cycle;
+ idata->rc->driver_name = IR_SPI_DRIVER_NAME;
+ idata->rc->priv = idata;
+ idata->spi = spi;
+
+ idata->negated = of_property_read_bool(spi->dev.of_node,
+ "led-active-low");
+ ret = of_property_read_u8(spi->dev.of_node, "duty-cycle", &dc);
+ if (ret)
+ dc = 50;
+
+ /* ir_spi_set_duty_cycle cannot fail,
+ * it returns int to be compatible with the
+ * rc->s_tx_duty_cycle function
+ */
+ ir_spi_set_duty_cycle(idata->rc, dc);
+
+ idata->freq = IR_SPI_DEFAULT_FREQUENCY;
+
+ return devm_rc_register_device(&spi->dev, idata->rc);
+}
+
+static int ir_spi_remove(struct spi_device *spi)
+{
+ return 0;
+}
+
+static const struct of_device_id ir_spi_of_match[] = {
+ { .compatible = "ir-spi-led" },
+ {},
+};
+
+static struct spi_driver ir_spi_driver = {
+ .probe = ir_spi_probe,
+ .remove = ir_spi_remove,
+ .driver = {
+ .name = IR_SPI_DRIVER_NAME,
+ .of_match_table = ir_spi_of_match,
+ },
+};
+
+module_spi_driver(ir_spi_driver);
+
+MODULE_AUTHOR("Andi Shyti <andi.shyti@samsung.com>");
+MODULE_DESCRIPTION("SPI IR LED");
+MODULE_LICENSE("GPL v2");