diff options
Diffstat (limited to 'drivers/media/dvb-frontends/isl6421.c')
| -rw-r--r-- | drivers/media/dvb-frontends/isl6421.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/drivers/media/dvb-frontends/isl6421.c b/drivers/media/dvb-frontends/isl6421.c new file mode 100644 index 000000000..2e9f6f12f --- /dev/null +++ b/drivers/media/dvb-frontends/isl6421.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * isl6421.h - driver for lnb supply and control ic ISL6421 + * + * Copyright (C) 2006 Andrew de Quincey + * Copyright (C) 2006 Oliver Endriss + * + * the project's page is at https://linuxtv.org + */ +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/slab.h> + +#include <media/dvb_frontend.h> +#include "isl6421.h" + +struct isl6421 { + u8 config; + u8 override_or; + u8 override_and; + struct i2c_adapter *i2c; + u8 i2c_addr; + bool is_off; +}; + +static int isl6421_set_voltage(struct dvb_frontend *fe, + enum fe_sec_voltage voltage) +{ + int ret; + u8 buf; + bool is_off; + struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv; + struct i2c_msg msg[2] = { + { + .addr = isl6421->i2c_addr, + .flags = 0, + .buf = &isl6421->config, + .len = 1, + }, { + .addr = isl6421->i2c_addr, + .flags = I2C_M_RD, + .buf = &buf, + .len = 1, + } + + }; + + isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1); + + switch(voltage) { + case SEC_VOLTAGE_OFF: + is_off = true; + break; + case SEC_VOLTAGE_13: + is_off = false; + isl6421->config |= ISL6421_EN1; + break; + case SEC_VOLTAGE_18: + is_off = false; + isl6421->config |= (ISL6421_EN1 | ISL6421_VSEL1); + break; + default: + return -EINVAL; + } + + /* + * If LNBf were not powered on, disable dynamic current limit, as, + * according with datasheet, highly capacitive load on the output may + * cause a difficult start-up. + */ + if (isl6421->is_off && !is_off) + isl6421->config |= ISL6421_DCL; + + isl6421->config |= isl6421->override_or; + isl6421->config &= isl6421->override_and; + + ret = i2c_transfer(isl6421->i2c, msg, 2); + if (ret < 0) + return ret; + if (ret != 2) + return -EIO; + + /* Store off status now in case future commands fail */ + isl6421->is_off = is_off; + + /* On overflow, the device will try again after 900 ms (typically) */ + if (!is_off && (buf & ISL6421_OLF1)) + msleep(1000); + + /* Re-enable dynamic current limit */ + if ((isl6421->config & ISL6421_DCL) && + !(isl6421->override_or & ISL6421_DCL)) { + isl6421->config &= ~ISL6421_DCL; + + ret = i2c_transfer(isl6421->i2c, msg, 2); + if (ret < 0) + return ret; + if (ret != 2) + return -EIO; + } + + /* Check if overload flag is active. If so, disable power */ + if (!is_off && (buf & ISL6421_OLF1)) { + isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1); + ret = i2c_transfer(isl6421->i2c, msg, 1); + if (ret < 0) + return ret; + if (ret != 1) + return -EIO; + isl6421->is_off = true; + + dev_warn(&isl6421->i2c->dev, + "Overload current detected. disabling LNBf power\n"); + return -EINVAL; + } + + return 0; +} + +static int isl6421_enable_high_lnb_voltage(struct dvb_frontend *fe, long arg) +{ + struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv; + struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0, + .buf = &isl6421->config, + .len = sizeof(isl6421->config) }; + + if (arg) + isl6421->config |= ISL6421_LLC1; + else + isl6421->config &= ~ISL6421_LLC1; + + isl6421->config |= isl6421->override_or; + isl6421->config &= isl6421->override_and; + + return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO; +} + +static int isl6421_set_tone(struct dvb_frontend *fe, + enum fe_sec_tone_mode tone) +{ + struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv; + struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0, + .buf = &isl6421->config, + .len = sizeof(isl6421->config) }; + + switch (tone) { + case SEC_TONE_ON: + isl6421->config |= ISL6421_ENT1; + break; + case SEC_TONE_OFF: + isl6421->config &= ~ISL6421_ENT1; + break; + default: + return -EINVAL; + } + + isl6421->config |= isl6421->override_or; + isl6421->config &= isl6421->override_and; + + return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO; +} + +static void isl6421_release(struct dvb_frontend *fe) +{ + /* power off */ + isl6421_set_voltage(fe, SEC_VOLTAGE_OFF); + + /* free */ + kfree(fe->sec_priv); + fe->sec_priv = NULL; +} + +struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr, + u8 override_set, u8 override_clear, bool override_tone) +{ + struct isl6421 *isl6421 = kmalloc(sizeof(struct isl6421), GFP_KERNEL); + if (!isl6421) + return NULL; + + /* default configuration */ + isl6421->config = ISL6421_ISEL1; + isl6421->i2c = i2c; + isl6421->i2c_addr = i2c_addr; + fe->sec_priv = isl6421; + + /* bits which should be forced to '1' */ + isl6421->override_or = override_set; + + /* bits which should be forced to '0' */ + isl6421->override_and = ~override_clear; + + /* detect if it is present or not */ + if (isl6421_set_voltage(fe, SEC_VOLTAGE_OFF)) { + kfree(isl6421); + fe->sec_priv = NULL; + return NULL; + } + + isl6421->is_off = true; + + /* install release callback */ + fe->ops.release_sec = isl6421_release; + + /* override frontend ops */ + fe->ops.set_voltage = isl6421_set_voltage; + fe->ops.enable_high_lnb_voltage = isl6421_enable_high_lnb_voltage; + if (override_tone) + fe->ops.set_tone = isl6421_set_tone; + + return fe; +} +EXPORT_SYMBOL_GPL(isl6421_attach); + +MODULE_DESCRIPTION("Driver for lnb supply and control ic isl6421"); +MODULE_AUTHOR("Andrew de Quincey & Oliver Endriss"); +MODULE_LICENSE("GPL"); |