diff options
Diffstat (limited to 'drivers/staging/comedi/drivers/comedi_8254.h')
| -rw-r--r-- | drivers/staging/comedi/drivers/comedi_8254.h | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/staging/comedi/drivers/comedi_8254.h b/drivers/staging/comedi/drivers/comedi_8254.h new file mode 100644 index 000000000000..d89f6d94f8aa --- /dev/null +++ b/drivers/staging/comedi/drivers/comedi_8254.h @@ -0,0 +1,133 @@ +/* + * comedi_8254.h + * Generic 8254 timer/counter support + * Copyright (C) 2014 H Hartley Sweeten <hsweeten@visionengravers.com> + * + * COMEDI - Linux Control and Measurement Device Interface + * Copyright (C) 2000 David A. Schleef <ds@schleef.org> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _COMEDI_8254_H +#define _COMEDI_8254_H + +/* + * Common oscillator base values in nanoseconds + */ +#define I8254_OSC_BASE_10MHZ 100 +#define I8254_OSC_BASE_5MHZ 200 +#define I8254_OSC_BASE_4MHZ 250 +#define I8254_OSC_BASE_2MHZ 500 +#define I8254_OSC_BASE_1MHZ 1000 +#define I8254_OSC_BASE_100KHZ 10000 +#define I8254_OSC_BASE_10KHZ 100000 +#define I8254_OSC_BASE_1KHZ 1000000 + +/* + * I/O access size used to read/write registers + */ +#define I8254_IO8 1 +#define I8254_IO16 2 +#define I8254_IO32 4 + +/* + * Register map for generic 8254 timer (I8254_IO8 with 0 regshift) + */ +#define I8254_COUNTER0_REG 0x00 +#define I8254_COUNTER1_REG 0x01 +#define I8254_COUNTER2_REG 0x02 +#define I8254_CTRL_REG 0x03 +#define I8254_CTRL_SEL_CTR(x) ((x) << 6) +#define I8254_CTRL_READBACK_COUNT ((3 << 6) | (1 << 4)) +#define I8254_CTRL_READBACK_STATUS ((3 << 6) | (1 << 5)) +#define I8254_CTRL_READBACK_SEL_CTR(x) (2 << (x)) +#define I8254_CTRL_LATCH (0 << 4) +#define I8254_CTRL_LSB_ONLY (1 << 4) +#define I8254_CTRL_MSB_ONLY (2 << 4) +#define I8254_CTRL_LSB_MSB (3 << 4) + +/* counter maps zero to 0x10000 */ +#define I8254_MAX_COUNT 0x10000 + +/** + * struct comedi_8254 - private data used by this module + * @iobase: PIO base address of the registers (in/out) + * @mmio: MMIO base address of the registers (read/write) + * @iosize: I/O size used to access the registers (b/w/l) + * @regshift: register gap shift + * @osc_base: cascaded oscillator speed in ns + * @divisor: divisor for single counter + * @divisor1: divisor loaded into first cascaded counter + * @divisor2: divisor loaded into second cascaded counter + * #next_div: next divisor for single counter + * @next_div1: next divisor to use for first cascaded counter + * @next_div2: next divisor to use for second cascaded counter + * @clock_src; current clock source for each counter (driver specific) + * @gate_src; current gate source for each counter (driver specific) + * @busy: flags used to indicate that a counter is "busy" + * @insn_config: driver specific (*insn_config) callback + */ +struct comedi_8254 { + unsigned long iobase; + void __iomem *mmio; + unsigned int iosize; + unsigned int regshift; + unsigned int osc_base; + unsigned int divisor; + unsigned int divisor1; + unsigned int divisor2; + unsigned int next_div; + unsigned int next_div1; + unsigned int next_div2; + unsigned int clock_src[3]; + unsigned int gate_src[3]; + bool busy[3]; + + int (*insn_config)(struct comedi_device *, struct comedi_subdevice *s, + struct comedi_insn *, unsigned int *data); +}; + +unsigned int comedi_8254_status(struct comedi_8254 *, unsigned int counter); +unsigned int comedi_8254_read(struct comedi_8254 *, unsigned int counter); +void comedi_8254_write(struct comedi_8254 *, + unsigned int counter, unsigned int val); + +int comedi_8254_set_mode(struct comedi_8254 *, + unsigned int counter, unsigned int mode); +int comedi_8254_load(struct comedi_8254 *, + unsigned int counter, unsigned int val, unsigned int mode); + +void comedi_8254_pacer_enable(struct comedi_8254 *, + unsigned int counter1, unsigned int counter2, + bool enable); +void comedi_8254_update_divisors(struct comedi_8254 *); +void comedi_8254_cascade_ns_to_timer(struct comedi_8254 *, + unsigned int *nanosec, unsigned int flags); +void comedi_8254_ns_to_timer(struct comedi_8254 *, + unsigned int *nanosec, unsigned int flags); + +void comedi_8254_set_busy(struct comedi_8254 *, + unsigned int counter, bool busy); + +void comedi_8254_subdevice_init(struct comedi_subdevice *, + struct comedi_8254 *); + +struct comedi_8254 *comedi_8254_init(unsigned long iobase, + unsigned int osc_base, + unsigned int iosize, + unsigned int regshift); +struct comedi_8254 *comedi_8254_mm_init(void __iomem *mmio, + unsigned int osc_base, + unsigned int iosize, + unsigned int regshift); + +#endif /* _COMEDI_8254_H */ |