1 // SPDX-License-Identifier: GPL-2.0-only
3  * IIO driver for the Measurement Computing CIO-DAC
6  * This driver supports the following Measurement Computing devices: CIO-DAC16,
7  * CIO-DAC08, and PC104-DAC06.
10 #include <linux/device.h>
32 static unsigned int base[max_num_isa_dev(CIO_DAC_EXTENT)];  variable
34 module_param_hw_array(base, uint, ioport, &num_cio_dac, 0);
35 MODULE_PARM_DESC(base, "Measurement Computing CIO-DAC base addresses");
40 static bool cio_dac_precious_reg(struct device *dev, unsigned int reg)  in cio_dac_precious_reg()
44 	 * the device, then no update occurs until a DAC register is read.  in cio_dac_precious_reg()
59  * struct cio_dac_iio - IIO device private data structure
60  * @map: Regmap for the device
70 	const unsigned int offset = chan->channel * CIO_DAC_CHANNEL_STRIDE;  in cio_dac_read_raw()
75 		return -EINVAL;  in cio_dac_read_raw()
77 	err = regmap_read(priv->map, CIO_DAC_BASE + offset, &dac_val);  in cio_dac_read_raw()
90 	const unsigned int offset = chan->channel * CIO_DAC_CHANNEL_STRIDE;  in cio_dac_write_raw()
93 		return -EINVAL;  in cio_dac_write_raw()
95 	/* DAC can only accept up to a 12-bit value */  in cio_dac_write_raw()
97 		return -EINVAL;  in cio_dac_write_raw()
99 	return regmap_write(priv->map, CIO_DAC_BASE + offset, val);  in cio_dac_write_raw()
114 static int cio_dac_probe(struct device *dev, unsigned int id)  in cio_dac_probe()  argument
122 		return -ENOMEM;  in cio_dac_probe()
124 	if (!devm_request_region(dev, base[id], CIO_DAC_EXTENT,  in cio_dac_probe()
126 		dev_err(dev, "Unable to request port addresses (0x%X-0x%X)\n",  in cio_dac_probe()
127 			base[id], base[id] + CIO_DAC_EXTENT);  in cio_dac_probe()
128 		return -EBUSY;  in cio_dac_probe()
131 	regs = devm_ioport_map(dev, base[id], CIO_DAC_EXTENT);  in cio_dac_probe()
133 		return -ENOMEM;  in cio_dac_probe()
136 	priv->map = devm_regmap_init_mmio(dev, regs, &cio_dac_regmap_config);  in cio_dac_probe()
137 	if (IS_ERR(priv->map))  in cio_dac_probe()
138 		return dev_err_probe(dev, PTR_ERR(priv->map),  in cio_dac_probe()
141 	indio_dev->info = &cio_dac_info;  in cio_dac_probe()
142 	indio_dev->modes = INDIO_DIRECT_MODE;  in cio_dac_probe()
143 	indio_dev->channels = cio_dac_channels;  in cio_dac_probe()
144 	indio_dev->num_channels = CIO_DAC_NUM_CHAN;  in cio_dac_probe()
145 	indio_dev->name = dev_name(dev);  in cio_dac_probe()
153 		.name = "cio-dac"
160 MODULE_DESCRIPTION("Measurement Computing CIO-DAC IIO driver");