2:34 PM PT -- If it seems like Tyrese Gibson was more heated than the situation called for, he tells TMZ there's a good reason he got so upset.
Tyrese says seconds before his interaction with the cashier, he'd been on the phone with his "best friend" Brandy Norwood to wish her a happy birthday -- and to console her, as it was also the 11th anniversary of her hero Whitney Houston's death.
He also told us he gave Home Depot "every opportunity in the world to clean this up, and they just refused."
Tyrese wants $1 million from Home Depot because he believes a cashier racially profiled him, and his whole exchange with her -- including a FaceTime call -- was captured on video.
The 'Fast & Furious' actor just filed the lawsuit on Thursday, but the incident went down back in February at a Home Depot in L.A.'s San Fernando Valley. In videos shot by Tyrese's team, the actor/singer explains to the cashier that he had authorized his team members to use his credit card to complete a purchase, but the cashier wouldn't let them.
Tyrese was not physically in the store at the time ... he says he left because too many customers were recognizing him, so he left his team with his credit card. The problem for the cashier -- as she repeatedly explained to Tyrese, who had FaceTime'd her -- is that she needed photo I.D. to go with his credit card.
He told the cashier he was just in the store 5 minutes earlier, and seems to be insinuating ... 'You can see my face, you know it's me, Tyrese.'
When the cashier insisted she needed his I.D., Tyrese did a little name-dropping as he threatened, "Should I have the CEO of Home Depot call you tomorrow? Because he's my neighbor in Atlanta."
The cashier never backed down, and Tyrese ended up going back to the store to complete the purchase, but not before having a lengthy standoff with the cashier and her manager.
In the lawsuit, obtained by TMZ, Tyrese he and his 2 team members -- Eric Mora and Manuel Hernandez -- have been in that Home Depot on "many occasions" over the years.
Tyrese says he's seeking $1 million, because that's how much he estimates he's spent at Home Depot over his lifetime. If that sounds like a lot, keep in mind ... he made some huge home improvements at the pad he sold last year -- dude built his own Benihana-style grill in the backyard!!!
He also wants punitive damages on top of the $1 mil.
For its part, Home Depot says, "Diversity and respect for all people are core to who we are, and we do not tolerate discrimination in any form. We value Mr. Gibson as a customer, and in the months since this happened, we've reached out to him and his attorneys several times to try to resolve his concerns. We will continue to do so."
It's unclear if Tyrese has discussed his grievances with his Atlanta neighbor.