1 // SPDX-License-Identifier: GPL-2.0-only
2 /* display7seg.c - Driver implementation for the 7-segment display
30 static int sol_compat = 0;		/* Solaris compatibility mode	*/
32 /* Solaris compatibility flag -
34  * documented driver features (ref Sun doc 806-0180-03).  
38  * 	1) Device ALWAYS reverts to OBP-specified FLIPPED mode
44  * omitting above features, set this parameter to non-zero.
51 MODULE_DESCRIPTION("7-Segment Display driver for Sun Microsystems CP1400/1500");
62  * Register block address- see header for details
63  * -----------------------------------------
65  * -----------------------------------------
67  * DP 		- Toggles decimal point on/off 
68  * ALARM	- Toggles "Alarm" LED green/red
69  * FLIP		- Inverts display for upside-down mounted board
70  * bits 0-4	- 7-segment display contents
77 		return -ENODEV;  in d7s_open()
86 	 * are not operating in solaris-compat mode  in d7s_release()
92 		regval = readb(p->regs);  in d7s_release()
93 		if (p->flipped)  in d7s_release()
97 		writeb(regval, p->regs);  in d7s_release()
106 	u8 regs = readb(p->regs);  in d7s_ioctl()
111 		return -ENODEV;  in d7s_ioctl()
116 		/* assign device register values we mask-out D7S_FLIP  in d7s_ioctl()
117 		 * if in sol_compat mode  in d7s_ioctl()
120 			error = -EFAULT;  in d7s_ioctl()
129 		writeb(ireg, p->regs);  in d7s_ioctl()
137 		 * of your hardware while in sol_compat mode  in d7s_ioctl()
140 			error = -EFAULT;  in d7s_ioctl()
146 		/* toggle device mode-- flip display orientation */  in d7s_ioctl()
148 		writeb(regs, p->regs);  in d7s_ioctl()
171 static int d7s_probe(struct platform_device *op)  in d7s_probe()  argument
174 	int err = -EINVAL;  in d7s_probe()
181 	p = devm_kzalloc(&op->dev, sizeof(*p), GFP_KERNEL);  in d7s_probe()
182 	err = -ENOMEM;  in d7s_probe()
186 	p->regs = of_ioremap(&op->resource[0], 0, sizeof(u8), "d7s");  in d7s_probe()
187 	if (!p->regs) {  in d7s_probe()
199 	/* OBP option "d7s-flipped?" is honored as default for the  in d7s_probe()
202 	regs = readb(p->regs);  in d7s_probe()
205 	    of_get_property(opts, "d7s-flipped?", NULL))  in d7s_probe()
206 		p->flipped = true;  in d7s_probe()
208 	if (p->flipped)  in d7s_probe()
213 	writeb(regs,  p->regs);  in d7s_probe()
215 	printk(KERN_INFO PFX "7-Segment Display%pOF at [%s:0x%llx] %s\n",  in d7s_probe()
216 	       op->dev.of_node,  in d7s_probe()
218 	       op->resource[0].start,  in d7s_probe()
219 	       sol_compat ? "in sol_compat mode" : "");  in d7s_probe()
221 	dev_set_drvdata(&op->dev, p);  in d7s_probe()
230 	of_iounmap(&op->resource[0], p->regs, sizeof(u8));  in d7s_probe()
236 static int d7s_remove(struct platform_device *op)  in d7s_remove()  argument
238 	struct d7s *p = dev_get_drvdata(&op->dev);  in d7s_remove()
239 	u8 regs = readb(p->regs);  in d7s_remove()
241 	/* Honor OBP d7s-flipped? unless operating in solaris-compat mode */  in d7s_remove()
243 		if (p->flipped)  in d7s_remove()
247 		writeb(regs, p->regs);  in d7s_remove()
251 	of_iounmap(&op->resource[0], p->regs, sizeof(u8));  in d7s_remove()